Document 5D8z60yzvY1QDoz49g8n957GJ

DEPARTMENT OF LABOUR Government Notice. R: 1179 25 August 1995 Hazardous Chemical Substances Regulations, 1995 The Minister of Labour has under section 43 of the Occupational Health and Safety Act, 1993 (Act No. 85 of 1993), after consultation with the Advisory Council for Occupational Health and Safety, made the regulations in the Schedule. SCHEDULE Definitions 1. In this Schedule a word or expression to which a meaning has been assigned in the Act shall bear the meaning so assigned to it and unless the context other-wise indicates - "air monitoring" means the monitoring of the concentrations of airborne hazardous chemical substances; "Asbestos Regulations" means the Asbestos Regulations published by Government Gazette No. R.773 of 10 April 1 987 under section 43(5) of the Act; "assessment" means a programme to determine any risk from exposure to a hazardous chemical substance associated with any hazard thereof at the workplace in order to identify the steps needed to be taken to remove, reduce or control such hazard; "BEI" or "biological exposure index" is a reference value intended as a guideline for the evaluation of potential health hazards as listed in Table 3 of Annexure 1 hereby as revised from time to time and listed in the Government Gazette; "engineering control measures" means control measures that remove or reduce the exposure of persons at the workplace by means of engineering methods; "exposed" means exposed to a hazardous chemical substance whilst at the workplace and "exposure" has a corresponding meaning; "EH 42" means the Guidance Note EH 42 of the Health and Safety Executive of the United Kingdom: Monitoring Strategies for Toxic Substances 1989 HSE ISBN 0 1188541 2 7 as revised from time to time and published in the Government Gazette; "Facilities Regulations" means the Facilities Regulations published by Government Notice No. R.2362 of 5 October 1990 under section 43(5) of the Act; "General Administrative Regulations" means the General Administrative Regulations published by Government Notice No. R.2206 of 5 October 1984 under section 43(5) of the Act; "HSC" or "hazardous chemical substance" means any toxic, harmful, corrosive, irritant or asphyxiant substance, or a mixture of such substances for which - (a) an occupational exposure limit is prescribed; or (b) an occupational exposure limit is not prescribed; but which creates a hazard to health; "intake" includes inhalation, ingestion or absorption through the skin or mucous membranes; "Lead Regulations" means the Lead Regulations published by Government Notice No. R.586 of 22 March 1991 under section 43(5) of the Act; "measurement programme" means a programme according to the monitoring strategy as contemplated in EH 42; "monitoring" means the planning, carrying out and recording of the results of a measurement programme; "OEL" or "occupational exposure limit" means a limit value set by the Minister for a stress factor in the workplace as revised from time to time by notice in the Government Gazette; "OEL-CL" or "occupational exposure limit-control limit" means the occupational exposure limit for a hazardous chemical substance as listed in Table 1 of Annexure 1 hereby and "control limit" has a corresponding meaning; "OEL-RL" or "occupational exposure limit-recommended limit" means the occupational exposure limit for a hazardous chemical substance as listed in Table 2 of Annexure 1 hereby and "recommended limit" has a corresponding meaning; "OESSM" means the Occupational Exposure Sampling Strategy Manual, published by the National Institute for Occupational Safety and Health (NIOSH), Publication No. 77-173 of 1977, United States of America: Department of Health, Education and Welfare; "regional director" means the regional director as defined in regulation 1 of the General Administrative Regulations; "respiratory protective equipment" means a devise which is worn over at least the mouth and nose to prevent the inhalation of airborne hazardous chemical substances and which is of a type, or conforms to a standard approved by the Minister; "respirator zone" means an area where the concentration of an airborne hazardous chemical substance exceeds the recommended limit for that substance; "SABS 072" the Code of Practice for the Safe Handling of Pesticides, SABS 072, published by the South African Bureau of Standards (SABS); "SABS 0228" the Code of Practice for the Identification and Classification of Dangerous Substances and Goods, SABS 0228, published by the South African Bureau of Standards (SABS); "SABS 0229" the Code of Practice for Packaging of Dangerous Goods for Road and Rail Transportation in South Africa, SABS 0229, published by the South African Bureau of Standards (SABS); Scope of application 2. (1) Subject to the provisions of sub-regulation (2), these regulations shall apply to an employer or a self employed person who carries out work at a workplace which may expose any person to the intake of an HCS at the workplace. (2) The provisions of regulations 3(1), 6 and 7 shall not apply to: (a) a self employed person; or (b) a person who visits a workplace as contemplated in subregulation (1). (3) The provisions of these regulations shall not apply in the case where the Lead Regulations and Asbestos Regulations apply . Information and training 3. (1) An employer shall, before any employee is exposed or may be exposed, after consultation with the health and safety committee established for that section of the workplace, ensure that the employee is adequately and comprehensively informed and trained, as well as thereafter informed and trained at intervals as may be recommended by that health and safety committee, with regard to: (a) the contents and scope of these regulations; (b) the potential source exposure; (c) the potential risks to health caused by exposure; (d) the potential detrimental effect of exposure on his or her reproductive ability; (e) the measures to be taken by the employers to protect an employee against any risk from exposure; (f) the precautions to be taken by an employee to protect himself against the health risks associated with such exposure, including the wearing and use of protective clothing and respiratory protective equipment. (g) the necessity, correct use, maintenance and potential of safety equipment, facilities and engineering control measures provided; (h) the necessity of personal air sampling and medical surveillance; (i) the importance of good housekeeping at the workplace and personal hygiene; (j) the safe working procedures regarding the use, handling, storage and labelling of the HCS at the workplace; and (k) procedures to be followed in the event of spillages, leakages or any similar emergency situation which could take place by accident. (2) An employer or self-employed person shall give written instructions of the procedures contemplated in paragraph (k) of subregulation (1) to the drivers of vehicles carrying the HCS. (3) An employer or a self employed person shall ensure that he himself or she herself or any other person who in any manner assists him or her in the carrying out or the conducting of his or her business, have the necessary information and has undergone sufficient training in order for him or her to identify the potential risks and precautions which should be taken. Duties of persons who may be exposed to hazardous chemical substances 4. Every person who is or may be exposed, shall obey a lawful instruction given by or on behalf of the employer or a self employed person, regarding: (a) the prevention of an HCS from being released; (b) the wearing of personal protective equipment; (c) the wearing of monitoring equipment to measure personal exposure; (d) the reporting for health evaluations and biological tests as required by these regulations; (e) the cleaning up and disposal of materials containing HCS; (f) housekeeping at the workplace, personal hygiene and environmental and health practices; and (g) information and training as contemplated in regulation 3. Assessment of potential exposure 5. (1) An employer or self employed person shall after consultation with the relevant health and safety representative or relevant health and safety committee, cause an immediate assessment to be made and thereafter at intervals not exceeding two years, to determine if any employee may be exposed by any route of intake. (2) The employer shall inform the relevant health and safety representative or relevant health and safety committee in writing of the arrangements made for the assessment contemplated in subregulation (1), give them reasonable time to comment thereon and ensure that the results of the assessment are made available to the relevant representatives or committees who may comment thereon. (3) When making the assessment, the employer or self employed person shall keep a record of the assessment and take into account such matters as: (a) the HCS to which an employee may be exposed; (b) what effects the HCS can have on an employee; (c) where the HCS may be present and in what physical form it is likely to be; (d) the route of intake by which and the extent to which an employee can be exposed; and (e) the nature of the work, process and any reasonable deterioration in, or failure of, any control measures. (4) If the assessment made in accordance with subregulation (3) indicates that any employee may be exposed, the employer shall ensure that monitoring is carried out in accordance with the provisions of regulations 6 and 7 and that the exposure shall be controlled as contemplated in regulation 10. (5) An employer shall review the assessment required by subregulation (1) forthwith if: (a) there is reason too suspect that the previous assessment is no longer valid; or (b) there has been a change in a process involving an HCS or in the methods, equipment or procedures in the use, handling, control or processing of the HCS, and the provisions of subregulations (2) and (3) shall apply. Air monitoring 6. (1) Where the inhalation of an HCS is concerned, an employer contemplated in regulation 5(4) shall ensure that the measurement programme of the airborne concentrations of the HCS to which an employee is exposed, is: (a) carried out in accordance with the provisions of these regulations; (b) carried out only after the relevant health and safety representative or relevant health and safety committee has been informed thereof and given a reasonable opportunity to comment thereon; (c) carried out by an approved inspection authority or by a person whose ability to do the measurements is verified by an approved inspection authority; (d) representative of the exposure of employees to the airborne HCS in accordance with the provisions of subregulation (2); and (e) verified in accordance with the provisions of subregulation (3) if the measurements are carried out by a person who is not an approved inspection authority. (2) In order to comply with the provisions of subregulation (1).(d) an employer shall; (a) ensure that the measurement programme, in the case of a group measurement, makes provision for the selection of the number of persons for a sample to be done as contemplated in chapters 3 and 4 and Technical Appendix A of the OESSM: Provided that such sample size shall be chosen for the top 10% of the group at the 95% confidence level for an HCS with a control limit and for the top 10% of the group at th 90% confidence level for an HCS with a recommended limit; and (b) carry out the representative measurements at least every 12 months for an HCS with a control limit and at least every 24 months for an HCS with a recommended limit: Provided that whenever the control limit or recommended limit which has been prescribed for an HCS is exceeded, the provisions of regulation 10 shall apply. (3) In order to comply with the provisions of subregulation (1).(e), an employer shall obtain the service of an approved inspection authority who shall, at intervals not exceeding 24 months: (a) verify, by examining the measurement and analysis equipment of the employer and questioning the person referred to in subregulation (1).(c), regarding the carrying out of the measurement programme; (b) carry out the measurements prescribed by subregulations (1) and (2) for any one group; and (c) enter the results of the investigation and measurements as contemplated in paragraphs (a) and (b) respectively in the record required by regulation 9. Medical surveillance 7. (1) An employer shall ensure that an employee is under medical surveillance if: (a) the employee may be exposed to a substance listed in Table 3 of Annexure 1; (b) the exposure of the employee to any substance hazardous to his or her health is such that an identifiable disease or adverse effect to his or her health may be related to the exposure, there is a reasonable likelihood that the disease or effect may occur under the particular conditions of his or her work and there are techniques to diagnose indications of the disease or the effect as far as is reasonably practicable; or (c) the occupational health practitioner recommends that the relevant employee should be under medical surveillance in which case the employer may call on an occupational medicine practitioner to ratify the appropriateness of such recommendation. (2) In order to comply with the provisions of subregulation (1) the employer shall, as far as is reasonably practicable, ensure: (a) that an initial health evaluation is carried out by an occupational health practitioner immediately before or within 14 days after a person commences employment, where any exposure exists or may exist, which comprises: (i) an evaluation of the employees medical and occupational history; (ii) a physical examination; and (iii) any other essential examination which in the opinion of the occupational health practitioner is desirable in order to enable the practitioner to do a proper evaluation. (b) that subsequent to the initial health evaluation contemplated in paragraph (a) the relevant employee undergoes examinations as contemplated in paragraph (a)(ii) and (iii), at intervals not exceeding two years, or at intervals specified by an occupational medical practitioner. (3) An employer shall not permit an employee who has been certified unfit for work by an occupational medicine practitioner to work in a workplace or part of a workplace in which he or she would be exposed: Provided that the relevant employee may be permitted to return to work which will expose him or her if he or she is certified fit for that work beforehand by an occupational medicine practitioner. (4) The employer shall record and investigate the incident contemplated in subregulation (3) in compliance with regulation 8 of the General Administrative Regulations. Respirator zone 8. An employer shall ensure: (a) that any workplace or part of a workplace under his or her control, where the concentration of an HCSHCS in the air is. or may be, such that the exposure of employees working in that workplace exceeds the recommended limit without the wearing of respiratory protective equipment, is zoned as a respirator zone; (b) that a respirator zone is clearly demarcated and identified by notice indicating that the relevant area is a respirator zone and that personal protective equipment as contemplated in regulation 11 must be worn there; and (c) that no person enters or remains in a respirator zone unless he or she is wearing the required personal protective equipment. Records 9. (1) An employer shall: (a) keep records of the results of all assessments, air monitoring, and medical surveillance reports required by regulations 5 , 6 and 7, respectively: Provided that personal medical records shall only be made available to an occupational health practitioner; (b) subject to the provisions of paragraph (c), make the records contemplated in paragraph (a), excluding personal medical records, available for inspection by an inspector. (c) allow any person subject to personal written consent of an employee, to peruse the records with respect to that particular employee; (d) make the records of all assessments and air monitoring available for perusal by the relevant health and safety representatives or relevant health and safety committee; (e) keep all records of assessments and air monitoring for a minimum period of 30 years; (f) keep all medical surveillance records for a minimum period of 30 years and if the employer ceases activities, all those records shall be handed over or forwarded by registered post to the relevant regional director; and (g) keep a record of the investigations and tests carried out in terms of regulation 12(1)(b) and of any repairs resulting from these investigations and tests, and the records shall be kept for at least three years. Handling of hazardous chemical substances 9A (1) Subject to section 10(3) of the Act, every person who manufactures, imports, sells or supplies any hazardous chemical substance for use at work, shall, as far as is reasonably practicable, provide the person receiving such substance, free of charge, with a material safety data sheet in the form of Annexure 1, containing all the information as contemplated in either ISO 1 1014 or ANSIZ400.1.1993 with regard to- (a) product and company identification; (b) composition/information on ingredients; (c) hazards identification; (d) first-aid measures; (e) fire-fighting measures; (f) accidental release measures; (g) handling and storage; (h) exposure control/personal protection; (i) physical and chemical properties; (j) stability and reactivity; (k) toxicological information; (l) ecological information; (m) disposal considerations; (n) transport information; (o) regulatory information; and (p) other information: Provided that, where it is not reasonably practicable to provide a material safety data sheet, the manufacturer, importer, seller or supplier shall supply the receiver of any hazardous chemical substance with sufficient information to enable the user to take the necessary measures as regards the protection of health and safety. (2) Every employer who uses any hazardous chemical substance at work, shall be in possession of a copy of Annexure 8 or a copy of sufficient information, as contemplated in subregulation (1). (3) Every employer shall make Annexure 8 or sufficient information, as contemplated in subregulation (1), available at the request of any interested or affected person. Control of exposure to HCS 10 (1) An employer shall ensure that the exposure of an employee is either prevented or, where this is not reasonably practicable, adequately controlled: Provided that (a) where there is exposure for which there is a recommended limit, the control of the exposure shall be regarded as adequate if the level of exposure is below that limit or if the relevant area is zoned and the level of exposure is reduced to below that recommended limit by means of adequate personal protective equipment only after the level has been reduced to as low as is reasonably practicable by any other means than personal protective equipment; or (b) where there is exposure for which there is a control limit, the control of the exposure shall be regarded as adequate if the exposure is at a a level as low as is reasonably practicable below that control limit: Provided that in the case of temporary excursions above the control limit, the employer shall ensure: (i) that the excursion is without a significant risk from exposure; (ii) that the excursion is not indicative of a failure to maintain adequate control; (iii) that during the excursion, the area is temporarily demarcated as prescribed in regulation 8(b) ; and (iv) the provisions of regulation 11 are complied with. (2) Where reasonably practicable, the employer shall control the exposure of an employee: (a) by limiting the amount of an HCS used which may contaminate the working environment; (b) by limiting the number of employees who will be exposed or may be exposed; (c) by limiting the period during which an employee will be exposed or may be exposed; (d) by using a substitute for an HCS; (e) by introducing engineering control measures for the control of exposure, which may include the following: (i) Process separation, automation or enclosure; (ii) the installation of local extraction ventilation systems to processes, equipment and tools for the control of emissions of an airborne HCS; (iii) use of wet methods; and (iv) separate workplaces for different processes; (f) by introducing appropriate work procedures which an employee must follow where materials are used or processes are carried out which could give rise to exposure of an employee and that procedures shall include written instructions to ensure: (i) that an HCS is safely handled, used and disposed of; (ii) that process machinery, installations, equipment, tools and local extraction and general ventilation systems are safely used and maintained; (iii) that machinery and work areas are kept clean; and (iv) that early corrective action can be readily identified. (3) An employer shall ensure that the emission of an HCS into the atmosphere comply with the provisions of the Atmospheric Pollution Prevention Act, 1965 (Act No. 45 of 1965). Personal protective equipment and facilities 11. (1) If it is not reasonably practicable to ensure that the exposure of an employee is adequately controlled as contemplated in regulation 10, the employer shall: (a) in the case of an airborne HCS, provide the employee with suitable respiratory protective equipment and protective clothing; and (b) in the case of an HCS which can be absorbed through the skin, provide the employee with suitable non-HCS impermeable protective equipment. (2) Where respiratory protective equipment is provided, the employer shall ensure: (a) that the relevant equipment is capable of controlling the exposure to below the OEL for the relevant HCS; (b) that the relevant equipment is correctly selected and properly used; (c) that information, instructions, training and supervision which is necessary with regard to the use of the equipment is known to the employees; and (d) that the equipment is kept in good condition and efficient working order. (3) An employer shall, as far as is reasonably practicable: (a) issue no used personal protective equipment to an employee, unless the relevant protection equipment is decontaminated and sterilised; (b) provide separate containers or storage facilities for personal protective equipment when not in use; and (c) ensure that all personal protective equipment not in use is stored only in the place provided therefor. (4) An employer shall as far as is reasonably practicable, ensure that all contaminated personal protective equipment is cleaned and handled in accordance with the following procedures: (a) where the equipment is cleaned on the premises of an employer, care shall be taken to prevent contamination during handling, transport and cleaning; (b) where the equipment is sent off the premises to a contractor for cleaning purposes: (c) the equipment shall be packed in impermeable containers; (d) the containers shall be tightly sealed and have clear indication thereon that the contents thereof are contaminated; and (e) the relevant contractor shall be fully informed of the requirements of these regulations and the precautions to be taken for the handling of the contaminated equipment. (5) Subject to the provisions of subregulation (4)(b) an employer shall ensure that no person removes dirty or contaminated personal protective equipment from the premises: Provided that where contaminated personal protective equipment has to be disposed of, it shall be treated as HCS waste as contemplated in regulation 15. (6) Subject to the provisions of the Facilities Regulations, an employer shall, where reasonably practicable, provide employees using personal protective equipment as contemplated in subregulation (1), with: (a) adequate washing facilities which are readily accessible and located in an area where the facilities will not become contaminated, in order to enable the employees to meet a standard of personal hygiene consistent with the adequate control of exposure, and to avoid the spread of an HCS; (b) two separate lockers separately labelled 'protective clothing' and 'personal clothing', and ensure that the clothing is kept separately in the locker concerned; (c) separate 'clean' and 'dirty' changerooms if the employer uses or processes an HCS to the extent that the HCS could endanger the health of persons outside of the workplace. Maintenance of control measures 12. An employer shall ensure: (a) that all control equipment and facilities provided in terms of regulations 10 and 11 are maintained in good working order; and (b) that thorough examinations and tests of engineering control measures are carried out at intervals not exceeding 24 months by an approved inspection authority or by a person whose ability to do such measurements and tests is verified by an approved inspection authority. Prohibitions 13. No person shall as far as is reasonably practicable: (a) use compressed air or permit the use of compressed air to remove particles of an HCS from any surface or person; and (b) smoke, eat, drink or keep food or beverages in a respirator zone or permit any other person to smoke, eat, drink or keep food or beverages in that zone. Labelling, packaging, transportation and storage 14. An employer shall, in order to avoid the spread of contamination of an HCS, take steps, as far as is reasonably practicable, to ensure: (a) that the HCS in storage or distributed are property identified, classified and handled in accordance with SABS 072 and SABS 0228; (b) that a container or a vehicle in which an HCS is transported is clearly identified, classified and packed in accordance with SABS 0228 and SABS 0229; and (c) that any container into which an HCS is decanted, is clearly labelled with regard to the contents thereof. Disposal of hazardous chemical substances 15. An employer shall, as far as is reasonably practicable: (a) recycle all HCS waste; (b) ensure that all collectable HCS waste is placed into containers that will prevent the likelihood of exposure during handling; (c) ensure that all vehicles, re-usable containers and covers which have been in contact with HCS waste are cleaned and decontaminated after use in such a way that the vehicles, containers or covers do not cause a hazard inside or outside the premises concerned; (d) ensure that all HCS waste which can cause exposure, is disposed of only on sites specifically designated for this purpose in terms of the Environmental Conservation Act, 1989 (Act No. 73 of 1989), in such a manner that it does not cause a hazard inside or outside the site concerned; (e) ensure that all employees occupied in the collection, transport and disposal of HCS waste, who may be exposed to that waste, are provided with suitable personal protective equipment; and (f) ensure that if the services of a waste disposal contractor are used, a provision is incorporated into the contract stating that the contractor shall also comply with the provisions of these regulations. Offences and Penalties 16. Any person who contravenes or fails to comply with any provision of regulation 3,4,5,6,7,8,9,9A, 10, 11, 12, 13,14 or 15 shall be guilty of an offence and liable on conviction to a fine or to imprisonment for a period not exceeding six months and, in the case of a continuous offence, to an additional fine of R200 for each day on which the offence continues or additional imprisonment of one day for each day on which the offence continuous: Provided that the period of such additional imprisonment shall in no case exceed 90 days. Short title 1 7. These regulations shall be called the Regulations for Hazardous Chemical Substances, 1995. ANNEXURE 1 HAZARDOUS CHEMICAL SUBSTANCES GUIDELINES Prevention and control of exposure 1. Exposure of employees to substances hazardous to health should be prevented or, where this is not reasonably practicable, adequately controlled. This is a fundamental requirement of the Regulations for Hazardous Chemical Substances (HCS), 1995. Exposure can occur by inhalation, ingestion or absorption through the skin, but inhalation is usually the main route of entry into the body. Tables 1 and 2 of Annexure 1 list the occupational exposure limits, which should be used in determining the adequacy of control of exposure by inhalation, as required by the HCS Regulations. 2. The advice in this document should be taken in the context of the requirements of the HCS Regulations, especially regulation 5 (Assessment of potential exposure) regulation 10 (Control of exposure), regulation 12 (Maintenance of control measures) and regulation 6 (Air monitoring). Substances hazardous to health are defined in regulation 1. There is separate legislation for lead and asbestos and these substances are not covered in detail in this document. This document also does not apply to exposure below ground in mines or exposure to micro-organisms. 3. Adequate control of exposure (when prevention is not reasonably practicable) should be achieved by one or more of a range of control measures described in regulation 10 of the HCS Regulations. Control by personal protective equipment should be applied only when other means are not reasonably practicable. Medical surveillance 4. Medical surveillance of employees is often an important addition to the control measures in the workplace, regulation 7(1) of the HCS Regulations specifies where medical surveillance is appropriate for the protection of the health of employees. 4.1 Medical surveillance is defined in the Regulations to cover the spectrum of potential effects of an HCS on an employee, from absorption of the substances through to clinical disease. Medical surveillance may be grouped broadly into- (a) biological monitoring, to measure the extent of absorption of an HCS by the employee. (b) medical screening, to detect any adverse affects of an HCS on the employee. 4.2 Biological monitoring of exposure 4.2.1 Objectives Biological monitoring of exposure can be divided into two types of testing: (a) Biological monitoring: Measures the bio-chemical concentrations of HCSs and/or their metabolites in biological samples of exposed individuals, e.g. blood lead for inorganic lead exposure, or urinary arsenic for inorganic arsenic exposure. The aim is to measure the degree of absorption into the body by measuring indicators in representative biological samples, typically urine or blood (usually nor related to the target organ). (b) Biological effect monitoring: Determines the intensity of biochemical or physiological change due to exposure, e.g. red cell cholinesterase for exposure to organosphosphate pesticides, or zinc protoporphyrin (ZPP) for exposure to inorganic lead. 4.2.2 Uses of biological monitoring Biological monitoring tests are indices of an individuals exposure and they may be a useful tool for the occupational health and safety team. They give information on the overall level of exposure, regardless of whether an HCS has been absorbed by the respiratory, oral, or cutaneous route. Cutaneous absorbtion can play a significant role in the case of some organic compounds. The amounts absorbed through the skin may be comparable to or even higher than those absorbed via the respiratory tract. Where appropriate, environmental control measures may thus be supplemented, with biological monitoring. Knowledge of the real individual exposure permits targeted applications of preventive measures. 4.2.3 Important considerations in biological monitoring (a) In choosing a test to meet the above objectives, it is important to have an understanding of the relationship between environmental exposure and the concentration of an HCS in biological samples. This includes an understanding of the principles of absorption, biotransformation, distribution and excretion of an HCS. (b) In addition, there should be analytical methods available of sufficient sensitivity and specificity to detect concentrations of the substance in urine, blood or exhaled air in the range likely to be encountered in industry. (c) The HCSs listed in Table 3 of Annexure 1 are those for which the above criteria have a reasonable chance of being met. 4.2.4 Biological Exposure Indices (BEIs) BEIs are reference values intended as guidelines for the evaluation of potential health hazards in the practice of industrial hygiene. A BEI represents in theory the level of an HCS or metabolite most likely to be observed in a specimen collected from a healthy worker who has been exposed to an HCS to the same extent as the worker with inhalation exposure to an OEL-TWA. BEIs do not represent a sharp distinction between hazardous and nonhazardous exposures. For example, owing to biological variability, it is possible that an individuals measurements can exceed the BEI without incurring an increased health risk. Conversely, there may be some susceptible individuals who may be harmed at effects below the BEI. If measurements in specimens obtained from a worker on different occasions persistently exceed the BEI, or if the majority of measurements in specimens obtained from a group of workers at the same workplace exceed the BEI, the cause of the excessive values must be investigated and proper action be taken to reduce the exposure. BEIs apply to eight-hour exposures, five days a week. However, BEIs for differing work schedules may be extrapolated on pharmacokinetic grounds. BEIs should not be applied either directly or through a conversion factor, in the determination of safe levels for non-occupational exposure to air and water pollutants, or food contaminants. The BEIs are not intended for use as a measure of adverse effects or for diagnosis of occupational illness. 4.3.1 Objectives (a) The principle of general medical screening is to detect a disease at an early subclinical or presymptomatic stage in order to take action to reverse these effects or to slow progression of the disease. The abnormalities sought, include pathophysiological or histopathological changes. Such tests are wellestablished in general preventative medicine, e.g. PAP smears for cervical cancer, cholesterol screening, feacal occult blood for lower bowel cancer, etc. (b) In medical surveillance in industry one is interested not only in detecting adverse effects in the individual, but also in the implication of the findings for the effectiveness of workplace control measures., Medical surveillance is thus directed not only at early adverse effects but also at established disease. 4.3.2 Types of examination (a) The number of validated screening tests with regard to HCSs is smaller than in general preventive medicine, but is likely to grow in the future. Examples of subclinical tests include urinary cytology for bladder cancer among workers exposed to potential bladder carcinogens, or full blood counts for employees exposed to an HCS toxic for the bloodforming organs. (b) Medical surveillance may include simple clinical examination, such as examination of the skin of employees exposed to contact irritants or allergens, or of the nasal septum of employees exposed to chromates. (c) Chest X-rays for silicosis are an example of screening for irreversible (although potentially progressive) disease. Lung function testing is well established as a non-specific test for the possible effect of respiratory irritants, sensitisers and fibrogenic agents. 4.4 Designing and implementing a programme of medical surveillance 4.4.1 The following steps should be included in any programme: (a) Risk assessment to determine the potential exposure to and routes of absorption of an HCS, as required by regulation 5. (b) Identification of target-organ toxicity, so as to direct medical screening. (c) Selection of appropriate tests and testing schedule. Tests should have the desirable operating characteristics of high sensitivity, specificity, reliability and predictive value. The frequency of testing is laid down in general terms by regulation 7 (2), but should in any case be based on an understanding of the nature of the hazard and the natural history of any adverse effects. (d) Development of action criteria. These are provided for some HCSs in the form of BEIs in Table 3 of Annexure 1. Criteria for interpreting lung function testing have also been published in the medical literature. However, in many cases, the occupational health practitioners will have to develop pragmatic criteria in the context of the specific workplace. (e) Standardisation of test process. Quality control needs to be exercised both in the testing site and in the laboratory contracted to carry out analyses. Consistency over time should be sought so as to make longitudinal measurements comparable. (f) Ethical considerations. Information and training of employees as required by regulation 3(1) should include the rationale for doing medical surveillance, and the consequence of abnormal findings. An employee must be notified of the results and interpretation of his/her tests and any recommendations made. The confidentiality of personal medical records is laid down by regulation 9. (g) Determination of employees fitness to remain in that job. [Regulation 7(3) ]. Results may be compared against the action criteria (BEI if relevant), and preferably also the employees previous results to determine whether individual action needs to be taken. Action may include repeating the test, further medical examination, removal of the employee from further exposure, and notification of the employer. Co-operation of employees can be best secured by a policy of protection of conditions of service in case of medical removal from a particular job. (h) Evaluation of control. An abnormal finding in an employee, or a pattern of findings in a group of employees, may point to inadequate primary control of exposure. In such cases the employer needs to be notified of such details of the medical findings as are necessary to evaluate the workplace problem and take remedial action. (i) Record keeping. This includes both medical records and exposure information for every employee. While the employer is responsible for record keeping in terms of regulation 9, the contents of personal medical records may be accessible to the occupational medicine practitioner, the employee, and any person nominated by the employee in writing. 4.4.2 The onus is on the occupational health practitioner carrying out medical surveillance to be familiar with the latest scientific information regarding the HCS and tests that might be useful. The aim should be to design a programme that is rational, ethical and effective. This may have to be done in the face of incomplete information of uncertainty regarding exposures, toxicity and test performance. Legal background to exposure limits 5. Two types of occupational exposure limits are defined in regulation 1 of the HCS Regulations. The two types are occupational exposure limit - control limit (OEL-CL), and occupational exposure limit - recommended limit (OEL-RL), as listed in Tables 1 and 2 of Annexure 1 (Table 1) (Table 2). The key difference between the two types of limits is that one OEL-RL is set at a level at which there is no indication of a risk to health; for an OEL-CL, a residual risk may exist and the level set, takes socio-economic factors into account. Further details are given in paragraphs 8 to 16. 6. Regulation 10 of the HCS Regulations lays down the requirements for the use of an OEL-CL and an OEL-RL for HCS for the purpose of achieving adequate control. Regulation 10(1) requires that, where there is exposure to a substance for which an OEL-CL is specified in Table 1 of Annexure 1, the control of exposure shall, so far as inhalation of that substance is concerned, be treated as adequate only if the level of exposure is reduced so far as is reasonably practicable and in any case below the OEL-CL. 7. Regulation 10(1) of the HCS Regulations requires that, where there is exposure to a substance for which an OEL-RL has been approved, the control of exposure shall, so far as inhalation of that substance is concerned, be treated as adequate if- (a) that OEL-RL is not exceeded; or (b) where that OEL-RL is exceeded, the employer identifies the reasons for the exceeding of the standard and takes appropriate action to remedy the situation as soon as is reasonably practicable. Setting occupational exposure limits Advisory Council and Standing Technical Committee 8. OEL-RL and OEL-CL are set by the chief inspector on recommendation of the Advisory Council for Occupational Health and Safety (the Advisory Council), following assessment by the Standing Committee No. 7 (TC7) of the Advisory Council for Occupational Health and Safety. 9. TC 7 must first consider what type of limit is appropriate, OEL-RL, or OELCL, and secondly, at what concentration the limit should be set. Setting an OEL-RL is the first option to be considered and TC 7 comes to a decision based on a scientific judgment of the available information on health effects. If, however, TC 7 decides that an OEL-CL is more appropriate, consideration of the level at which to set the limit passes to the Advisory Council, since it involves socio-economic judgments, balancing risk to health against the cost and effort of reducing exposure. Following public consultation, new OEL-CLs and OEL-RLs are listed in Table 1 and Table 2 of Annexure 1 respectively with the approval of the chief inspector. The indicative criteria 10. An OEL-RL can be assigned to a substance, if all three of the following criteria are complied with: There is a no-risk at the exposure limit Criterion 1: The available scientific evidence allows for the identification, with reasonable certainty, of a concentration averaged over a reference period, at which there is no indication that the substance is likely to be injurious to employees if they are exposed by inhalation day after day to that concentration. Likely excursions above the exposure limit are unlikely Criterion 2: Exposure to concentrations higher than that derived under criterion 1 and which could reasonably occur in practice, is unlikely to produce serious short or long-term effects on health over the period of time it might reasonably be expected to take to identify and remedy the cause of excessive exposure. Compliance is reasonably practicable Criterion 3: The available evidence indicates that compliance with an OELRL, as derived under criterion 1, is reasonably practicable. 11. A substance which does not meet criteria 1, 2 and 3, can be assigned an OEL-CL and must meet either of the following criteria: Criterion 4: The available evidence on the substance does not satisfy criterion 1 and/or 2 for an OEL-RL and exposure to the substance has, or is liable to have, serious health implications for workers; or Criterion 5: Socio-economic factors indicate that although the substance meets criteria 1 and 2 for an OEL-RL, a numerically higher value is necessary if the controls associated with certain uses are to be regarded as reasonably practicable. Setting an OEL-RL 1 2. Criterion 1 sets out the fundamental basis for establishing such a limit: The existence of a threshold above which there may be evidence of significant effects on health but below which, on existing knowledge, there are thought to be no adverse effects. 13. Criterion 2 is necessary in order to take account of HCS Regulation 10(1) of the HCS Regulations whereby exposures above an OEL-RL are allowed provided the employer identifies the reasons for exceeding the standard and takes steps to reduce exposure to that OEL-RL as soon as is reasonably practicable. Clearly, it is necessary to take account of the likelihood and probable extent of cases in deciding whether an OEL-RL is appropriate. The health effects to be taken into account include sensory and other effects such as the slowing of reflexes which might result in the impairment of safety. 14. Criterion 3 takes account of whether industry can reasonably comply with the exposure limit derived under the first criterion. There is no purpose in setting an OEL-RL which plainly cannot be achieved in practice. Note that industry's ability to comply, influences the decision of whether to set an OELRL, but does not influence the level at which that OEL-RL is set. Setting an OEL-CL 15. To be assigned an OEL-RL, a substance must meet all the first three criteria; if it does not, then it can be considered for an OEL-CL. To be assigned an OEL-CL, there should be serious implications for the health of workers exposed to the substance. Serious health implications include both the risk of serious health effects to a small population of workers and the risk of relatively minor health effects to a large population. In practice, an OEL-CL has been most often allocated to carcinogens and to other substances for which no threshold of effect can be identified and about which there is no doubt about the seriousness of the effects of exposure. 16. An OEL-CL and an OEL-RL, therefore, differ not only in their legal status, but also in the way in which they are set. For an OEL-RL the only consideration in setting the limits is the protection of the health of the employee; for an OEL-CL this is still the primary consideration but socio economic factors are also taken into account. 17. The indicative criteria, than, provide the framework within which the discussions at the various stages of limit-setting can be conducted. Applying occupational exposure limits General 18. The lists of occupational exposure limits given in Table 1 and Table 2 of Annexure 1, unless otherwise stated, relate to personal exposure to substances hazardous to health in the air of the workplace. Units of measurement 19. In occupational exposure limits, concentrations of gases and vapours in air are usually expressed in parts per million (ppm), a measure of concentration by volume, as well as in milligrams per cubic metre of air (mg/m3), a measure of concentration by mass. In converting from ppm to mg/m3 a temperature of 25C and an atmospheric pressure of 101.325 kPa are used. Concentrations of airborne particles (fume, dust, etc.) are usually expressed in mg/m3. In the case of dust, the limits in the tables refer to the total inhalable fraction unless specifically indicated as referring to the respirable fraction (see paragraph 36). In the case of a man-made mineral fibre, the limit is expressed as fibres per millilitre of air (fibres/ml). Occupational exposure limits - control limits: OEL-CL (table 1) 20. An OEL-CL is the maximum concentration of an airborne substance, averaged over a reference period, to which employees may be exposed by inhalation under any circumstances, and is specified together with the appropriate reference period in Table 1 of Annexure 1. 21. Regulation 19(1) of the HCS Regulations, when read in conjunction with the Act, imposes a duty on the employer to take all reasonable precautions and to exercise all due diligence to ensure that exposure is kept as far below an OEL-CL as is reasonably practicable. 22. To comply with this duty, in the case of substances with a 8-hour reference period, employers should undertake a programme of monitoring in accordance with regulation 6 so that they can show (if it is the case), that an OEL-CL is not exceeded. Such a monitoring programme need not be undertaken if the assessment carried out in accordance with regulation 5 shows that the level of exposure is most unlikely ever to exceed an OEL-CL. For substances assigned a short-term limit, such value should never be exceeded. 23. The assessment should also be used to determine the extent to which it is reasonably practicable to reduce exposure further below an OEL-CL as required by regulation 10(1) In assessing reasonable practicability, the nature of the risk presented by the substance in question should be weighed against the cost and the effort involved in taking measures to reduce the risk. (Also see the definition of reasonably practicable as defined in the Act.) Occupational exposure limit-recommended limit: OEL-RL (Table 2) 24. An OEL-RL is the concentration of an airborne substance, averaged over a reference period, at which, according to current knowledge, there is no evidence that it is likely to be injurious to employees if they are exposed by inhalation, day after day, to that concentration. 25. For a substance, which has been assigned an OEL-RL, exposure by inhalation should be reduced to that standard. However, if exposure by inhalation exceeds the OEL-RL, then control will still be deemed to be adequate provided that the employer has identified why the OEL-RL has been exceeded and is taking appropriate steps to comply with the OEL-RL as soon as reasonably practicable. In such a case, the employers objective must be to reduce exposure to the OEL-RL, but the final achievement of this objective may take some time. The assessment under regulation 5 will determine the urgency of the necessary action, taking into account the extent and cost of the required measures in relation to the nature and degree of exposure involved. 26. Control of an OEL-RL as prescribed in regulation 10 (1) (a) can always be regarded as adequate control of that substance for the purpose of the HCS Regulations, so far as exposure from inhalation is concerned. However, due to the variations in process control and the fluctuations in substance concentrations in the workplace, it will be prudent for employers to reduce exposure below an OEL-RL as to ensure that the exposure of all employees does not exceed that OEL-RL. Similarly, it is not intended that the statutory requirements under regulation 10 (1) should discourage the further application of good occupational hygiene principles in order to reduce exposure below the OEL-RL. Long-term and short-term exposure limits 27. The pattern of effects due to exposure to substances hazardous to health varies considerably depending on the nature of the substance and the exposure. Some effects require prolonged or accumulated exposure. The long-term (8-hour time weighted average) exposure limit is intended to control such effects by restricting the total intake by inhalation over one or more workshifts. Other effects may be seen after brief exposures which have occurred once or repeatedly. Short-term limits (usually 15 minute) may be applied to such substances. Where long-term limits also apply, the short-term limits restrict the magnitude of excursion above the average concentration during longer exposures. For those substances for which no short-term limit is specified, it is recommended that a figure of three times the long-term limit be used as a guideline for controlling short-term excursions in exposure. With some other substances, brief exposure may be critical and the exposure limit necessary to prevent these excursions will also control any other effects. A separate long-term limit is not considered necessary in such cases and the short-term limit applies throughout the shift. 28. Exposure limits are expressed as airborne concentrations averaged over a specified period of time. The period for the long-term limit is normally eight hours. When a different period is used, this is stated. The averaging period for the short-term exposure limit is normally 15 minutes. Such a limit applies to any 15 minute period throughout the working shift. Limitations to the application of exposure limits 29. The exposure limits relate to personal exposure with the exception of the annual OEL-CL for vinyl chloride which should be recorded as the timeweighted average of vinyl chloride in the atmosphere of a working place over a period of one year (see Annexure 2) and the OEL-RL for cotton dust is not a personal exposure standard, but a static air standard (see Annexure 4). 30. The limits cannot readily be extrapolated to evaluate or control nonoccupational exposure, e.g. levels of contamination in the neighbourhood close to an industrial plant. OELs only apply to persons at work. Employers should also take into account their duties under the Environmental Protection Act. The OELs are also only approved for use where the atmospheric pressure is between 85 kPa and 101.325 kPa. This covers the normal range of meteorological variations and slightly pressurised workplaces such as cleaning rooms, but not the higher pressures that may be encountered in, for example, tunnelling or underwater hyperbaric chambers. Such situations require special assessments. 31. Occupational exposure limits, as set out in Tables 1 and 2 of Annexure 1, are intended to be used for normal working conditions in workplaces. Employers should also take into account their duties and the provisions of the Environmental Conservation Act. OELs are not, however, designed to deal with serious accidents or emergencies, particularly where employees may be exposed to rapidly rising concentrations of gas, as may arise from a major escape due to plant failure. Over and above their responsibilities to ensure that the requirements of the HCS Regulations are met, employers also have a clear responsibility to ensure that the plant is designed, operated and maintained in a way that avoids accidents and emergencies. Where appropriate, detection, alarm and response measures should be used in order to minimise the effect of any such unplanned events. 32. To help maintain adequate operational control, employers may find it helpful to select their own indicators of control when undertaking investigations or corrective action. Exposure in mines 33. The HCS Regulations and the occupational exposure limits in this publication do not apply to exposure to substances hazardous to health in mines. Lead and asbestos 34. Work with asbestos or lead is not subject to the HCS Regulations. The exposure limits for various types of asbestos and lead are specified in the Asbestos Regulations and the Lead Regulations. Pesticides 35. Substances used as active ingredients in pesticides are listed under their chemical names and/or their common (ISO) names. These names may sometimes be used as parts of the names of proprietary pesticide formulations. In all cases the exposure limit applies to the specific active ingredients and not to the formulation as a whole. Dusts 36. The general approach necessary to control occupational exposure to dusts is as follows: not all dusts have been assigned occupational exposure limits but the lack of such limits should not be taken to imply an absence of hazard. In the absence of a specific exposure limit for a particular dust, exposure should be adequately controlled. Where there is no indication of the need for a lower value, personal exposure should be kept below both 10 mg/m3 8-hour time-weighted average total inhalable dust and 5 mg/m3 timeweighted average respirable dust. Such, or greater, dust concentrations should be taken as the substantial concentrations. A substantial concentration of dust should be taken as a concentration of 10 mg/m3, 8-hour time-weighted average, of respirable dust, where there is no indication of the need for a lower value, and as such they are referred to as substances hazardous to health. Total inhalable dust and respirable dust 37. Total inhalable dust approximates to the fraction of airborne material that enters the nose and mouth during breathing and is therefore available for deposition in the respiratory tract. Respirable dust approximates to the fraction which penetrates to the gas exchange region of the lung. A fuller definition is given at the end of Table 2 of Annexure 1 (Abbreviations). 38. Where dusts contain components which have their own assigned occupational exposure limits, all the relevant limits should be complied with. Fume 39. Where a separate OEL has been set for fume, it should normally be applied to solid particles generated by chemical reactions or condensed from the gaseous state, usually after volatilisation from melted substances. The generation of fume is often accompanied by a chemical reaction such as oxidation or thermal breakdown. Absorption through the skin 40. In general, for most substances the main route of entry into the body is by inhalation. The OELs given in these regulations solely relate to exposure by this route. Certain substances such as phenol, aniline and certain pesticides (marked in the Tables with an SK notation) have the ability to penetrate the intact skin and thus become absorbed into the body. Absorption through the skin can result from localised contamination, for example, from a splash on the skin or clothing, or in certain cases from exposure to high atmospheric concentrations of vapour. Serious effects can result in little or no warning and it is necessary to take special precautions to prevent skin contact when handling these substances. Where the properties of the substances and the methods of use provide a potential exposure route via skin absorption, these factors should be taken into account in determining the adequacy of the control measures. Sensitisers 41. Certain substances may cause sensitisation of the respiratory tract if inhaled or skin contact occurs. Respiratory sensitisers can cause asthma, rhinitis, or extrinsic allergic alveolitis. Skin sensitisers cause allergic contact dermatitis. Substances which cause skin sensitations are not necessarily respiratory sensitisers or vice-versa. Only a proportion of the exposed population will become sensitised, and those who do become sensitised, will not have been identified in advance. Individuals who become sensitised may produce symptoms of ill health after exposure even to minute concentrations of the sensitiser. 42. Where it is reasonably practicable, exposure to sensitisers should be prevented. Where this cannot be achieved, exposure should be kept as low as is reasonably practicable and activities giving rise to short-term peakconcentrations should receive particular attention. As with other substances, the spread of contamination by sensitisers to other working areas should also be prevented, as far as is reasonably practicable. 43. The Sen notation (marked in the Tables with a Sen notation) has been assigned only to those sensitisers that may cause sensitisation by inhalation. Remember that other substances not contained in these Tables can act as respiratory sensitisers. Other factors 44. Working conditions which impose additional stress on the body, such as exposure to ultra-violet radiation, high temperatures, pressures and humidity, may increase the toxic response to a substance. In such cases, specialist advice may be necessary to evaluate the effect of these factors. Mixed Exposures General 45. The majority of OELs listed in Tables 1 and 2 of Annexure 1 are for single compounds or for substances containing a common element or radical, e.g. tungsten and compounds, and isocyanates. A few of the limits relate to substances commonly encountered as complex mixtures or compounds e.g. white spirit, rubber fume, and welding fume. However, workers are frequently subject to other mixed exposures involving solids, liquids, aerosols or gases. These exposures can arise as a result of work with materials containing a mixture of substances, or from work with several individual substances, simultaneously or successively, in a workshift. Mixed exposures require careful assessment of their health effects and the appropriateness of control standards. The following paragraphs provide a brief summary of the advice on the application of exposure limits in these circumstances. In all cases of doubt, specialist advice should be sought. Effects of mixed exposures 46. The ways in which the constituent substances of a mixed exposure interact, vary considerably. Some mixed exposures involve substances that act on different body tissues or organs, or by different toxilogical mechanisms, these various effects being independent of each other. Other mixtures will include substances that act on the same organs, or by similar mechanisms, so that the effects reinforce each other and the substances are additive in their effect. In some cases the overall effect is considerably greater than the sum of the individual effects and the system is synergistic. This may arise from mutual enhancement of the effects of the constituents or because one substance potentiates another, causing it to act in a way which it would not do alone. Assessment and control 47. With All types of mixed exposures, it is essential that assessments be based on the concentrations of each of the constituents in air to which workers are exposed. Depending on the nature of the constituents and the circumstances of use, the relative concentrations of the constituents in air may differ considerably from those in the liquid or solid source material. The composition of the bulk material should not be relied on for assessment unless there is good evidence for doing so. 48. Where mixed exposures occur, the first step is to ensure adequate control of exposure for each individual substance. However, the nature and amount of the other substances in a mixture can influence the level to which it is reasonably practicable to reduce exposure to a substance subject to an OELCL. When limits for specific mixtures have been established, they should be used only where they are applicable, and in addition to any relevant individual limits. They should not be extended to inappropriate situations. It is then necessary to assess whether further control is needed to counteract any increased risk from the substances acting in conjunction. Expert assessments for some particular mixed exposures may be available and can be used as guidelines in similar cases. In other cases, close examination of the toxicological data will be necessary to determine which of the main types of interaction (if any) are likely for the particular combination of substances concerned. The various types should be considered in the following order: (a) Synergistic substances: Known cases of synergism and potentiation are considerably less common than the other types of behaviour in mixed exposures. However, they are the most serious in their effects and require the most strict control. They are also the most difficult to assess and wherever there is reason to suspect such interaction, specialist advice should be obtained; (b) Additive substances: Where there is reason to believe that the effects of the constituents are additive, and where the exposure limits are based on the same health effects, the mixed exposure should be assessed by means of the formula- here C1, C2, etc. are the time-weighted average (TWA) concentrations of constituents in air and L1, L2, etc are the corresponding exposure limits. The use of this formula is only applicable where the additive substances have been assigned OELs, and L1, L2, etc. relate to the same reference period in the list of approved OELs. Where the sum of the C/L fractions does not exceed one, the exposure is considered not to exceed the national OELs. If one of the constituents has been assigned an OEL-CL, then the additive effect should be taken into account in deciding the extent to which it is reasonably practicable to further reduce exposure; and (c) Independent substances: Where no synergistic or additive effects are known or considered likely, the constituents can be regarded as acting independently. It is then sufficient to ensure compliance with each of the OELs individually. 49. The above steps provide basic protocol for assessment of mixed exposures. It is open to persons responsible for control of exposure to treat all non-synergistic systems as though they were additive. This avoids the need to distinguish additive and independent systems and can be regarded as the most prudent course, particularly where the toxicity data are scarce or difficult to assess. Monitoring mixed exposure 50. Further information on monitoring airborne contaminants is given in paragraphs 52 and 53. The number of components of a mixed exposure for which routine air monitoring is required, can be reduced if their relative concentrations can be shown to be constant. This involves the selection of a key or marker, which may be one of the constituents, as a measure of the total contamination. Exposure to the marker is controlled at a level selected so that exposures to all components will be controlled in accordance with the criteria in paragraphs 48(a) and (b). However, if one of the components has been assigned an OEL-CL, the level of the exposure to that substance should always be reduced as far as is reasonably practicable. If this approach is to be used, it should take place under the guidance of suitable specialist advice. Complicating factors 51. Several factors that complicate the assessment and control of exposure to individual substances will also affect cases of mixed exposures and will require similar special consideration. Such factors include- (a) exposure to a substance for which there is no established limit or for which an OEL-CL has been set; (b) the relevance of factors such as alcohol, medication, smoking and additional stresses; (c) exposure of the skin to one or more substances that can be absorbed by this route, as well as by inhalation; and (d) substances in mixture may mutually affect the extent of their absorption, as well as their health effects, at a given level of exposure. Monitoring exposure 52. Regulation 5 (4) of the HCS Regulations imposes a duty on the employer to monitor the exposure of employees to substances hazardous to health. 53. Details of routine sampling strategies for individual substances are outside the scope of this document. However, advice is available in EH 42, which provides practical guidance on monitoring substances hazardous to health in air. Biological Exposure Indices Acetone Determinant Acetone in urine Sampling Time End of shift BEI 100 mg/l Notation B,C Aniline Determinant Total p-aminophenol in urine Sampling Time End of shift BEI 50 mg/g creatinine Notation C Determinant Methemoglobin in blood Sampling Time During or end of shift BEI Notation 1.5% of hemoglobin B, C , D Arsenic and soluble compounds, including Arsine Determinant Inorganic arsenic metabolites in urine Sampling Time End of workweek BEI Notation 50 ug/g creatinine B Benzene Determinant Total phenol in urine Sampling Time End of shift BEI 50 mg/g creatinine Notation B, C Benzene in exhaled air: Determinant Mixed exhaled Sampling Time Prior to next shift BEI Notation 0.08 ppm D Determinant End exhaled BEI 0.12 ppm Cadmium Determinant Cadmium in urine Sampling Time Not critical BEI 10 ug/g creatinine Notation B Determinant Cadmium in blood Sampling Time Not critical BEI 10 ug/l Notation B Carbon Disu lphide Determinant Sampling Time BEI 2-Thiothiazolidine-4-carboxylic acid (TTCA) in urine End of shift 5 mg/g creatinine Carbon Monoxide Determinant Carboxyhemoglobin in blood Sampling Time End of shift BEI < 8 % of hemoglobin Notation B, C Determinant CO in end exhaled air Sampling Time BEI Notation End of shift < 40 ppm B, C Chlorobenzene Determinant Total 4-chlorocatechol in urine Sampling Time End of shift BEI 150 mg/g creatinine Notation C Determinant Total p-chlorophenol in urine Sampling Time End of shift BEI 25 mg/g creatinine Notation C Chromium (VI) Determinant Water soluble fume Sampling Time Increase during shift BEI 10 ug/g creatinine Notation B Determinant Total chromium in urine Sampling Time End of shift at end of workweek BEI 30 ug/g creatinine Notation B N,N-Dimethylformamide (DMF) Determinant N-Methylformamide in urine Sampling Time End of shift BEI Notation 40 mg/g creatinine B 2-Ethoxyethanol (EGEE) Determinant 2-Ethoxyacetic acid in Sampling Time BEI urine End of shift at end of workweek 100 mg/g creatinine 2-Ethoxyethylacetate (EGEEA) Determinant Sampling Time BEI 2-Ethoxyacetic acid in urine End of shift at end of workweek 100 mg/g creatinine Ethyl Benzene Determinant Mandelic acid in urine Sampling Time End of shift at end of workweek BEI Notation 1.5 g/g creatinine A Determinant Notation Ethyl benzene in end exhaled air D Flourides Determinant Flourides in urine Sampling Time Prior to shift BEI Notation 3 mg/g creatinine B, C Sampling Time BEI Notation End of shift 10 mg/g creatinine B, C Furfural Determinant Total furoic acid in urine Sampling Time End of shift BEI Notation 200 mg/g creatinine B, C n-Hexane Determinant 2,5-Hexanedione in urine Sampling Time BEI Notation End of shift 5 mg/g creatinine C Determinant n-Hexane in endexhaled air Notation D Lead Determinant Sampling Time BEI Notation Lead in blood Not critical 50 ug/100 ml B Determinant Sampling Time BEI Notation Lead in urine Not critical 150 ug/g creatinine B Determinant Sampling Time BEI Notation Zinc protoporphyrin in blood After 1 month exposure 250 ug/100 ml erythrocytes or 100 ug/100ml blood B Mercury Determinant Sampling Time BEI Notation Total inorganic mercury in urine Preshift 35 ug/g creatinine B Determinant Total inorganic mercury in blood Sampling Time End of shift at end of workweek BEI 15 ug/l Notation B Methanol Determinant Sampling Time Methanol in urine End of shift BEI Notation 15 mg/l B, C Determinant Sampling Time BEI Notation Formic acid in urine Prior to last shift of workweek 80 mg/g creatinine B, C Methemoglottin inducers Determinant Methemeglobin in blood Sampling During or end of Time shift BEI 1.5% of hemoglobin Notation B, C , D Methyl Chloroform Determinant Methyl chloroform in end exhaled air Sampling Time Prior to last shift of workweek BEI 40 ppm Determinant Sampling Time BEI Notation Trichloroacetic acid in urine End of workweek 10 mg/l C, D Determinant Sampling Time BEI Notation Total trichloroethanol in urine End of shift at end of workweek 30 mg/l C, D Determinant Total trichloroethanol in blood Sampling Time End of shift at end of workweek BEI 1 mg/l Notation C Methyl Ethyl Ketone (MEK) Determinant MEK in urine Sampling Time End of shift BEI 2 mg/l Methyl isobutyl ketone (MIBK) Determinant MIBK in urine Sampling Time End of shift BEI 2 mg/l Nitrobenzene Determinant Total p-nitrophenol in urine Sampling Time End of shift at end of workweek BEI 5 mg/g creatinine Notation C Determinant Sampling Time BEI Notation Methemoglobin in blood End of shift 1.5% of hemoglobin B, C , D Organophosphorus Cholinesterase Inhibitors Determinant Cholinesterase activity in red cells Sampling Time Discretionary BEI Notation 70% of individual's baseline B, C , D Parathion Determinant Sampling Time Total p-nitrophenol in urine End of shift BEI 0.5 mg/g creatinine Notation C, D Determinant Sampling Time BEI Notation Cholinesterase activity in red cells Discretionary 70% of individuals baseline B, C , D Pentachlorophenol Determinant Sampling Time Total PCP in urine Prior to the last shift of workweek BEI Notation 2 mg/g creatinine B Determinant Sampling Time BEI Notation Free PCP in plasma End of shift 5 mg/l B Perchloroethylene Determinant Perchloroethylene in endexhaled air Sampling Time Prior to the last shift of workweek BEI 10 ppm Determinant Perchloroethylene in blood Sampling Time Prior to the last shift of workweek BEI 1 mg/l Determinant Trichloroacetic acid in urine Sampling Time End of workweek BEI 7 mg/l Notation C, D Phenol Determinant Total phenol in urine Sampling Time End of shift BEI 250 mg/g creatinine Notation B, C Styrene Determinant Sampling Time Mandelic acid in urine End of shift BEI 800 mg/g creatinine Notation C Sampling Time BEI Notation Prior to next shift 300 mg/g creatinine C Determinant Phenolglyoxylic acid in urine Sampling Time End of shift BEI 240 mg/g creatinine Notation B, C Sampling Time BEI Notation Prior to next shift 100 mg/g creatinine B, C Determinant Styrene in venous blood Sampling Time End of shift BEI 0.55 mg/l Notation D Sampling Time BEI Notation Prior to next shift 0.02 mg/l DD Toluene Determinant Sampling Time BEI Notation Hippuric acid in urine End of shift Last 4 hours of shift 2.5 g/g creatinine B, C Determinant Sampling Time BEI Notation Toluene in venous blood End of shift 1 mg/l D Determinant Sampling Time BEI Notation o-Cresol in urine End of shift 1 mg/g creatinine C ene Determinant Sampling Time Trichloroacetic acid in urine End of workweek BEI Notation 100 mg/g creatinine C Determinant Trichloroacetic acid and trichloroethanol in urine Sampling Time BEI Notation End of shift at end of workweek 300 mg/g creatinine C Determinant Sampling Time BEI Notation Free trichloroethanol in blood End of shift at end of workweek 4 mg/l C Determinant Trichloroethylene in end-exhaled air Notation D Xylenes_____ Determinant Methylhippuric acid in urine Sampling Time End of shift Last 4 hours of shift BEI 1.5 g/g creatinine Notation 2 mg/min Carcinogenic Compounds Substance Acetaldehyde CH3CHO Acrylamide CH2=CHCONH2 Acrylonitrile CH2=CHCN Aldrin C12H8Cl6 Allyl Chloride CH2=CHCH2Cl 4-Aminodiphenyl Carcinogenicity Animal Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Confirmed Human Carcinogen Amitrole Suspected Human Carcinogen Aniline and homologues C6H5NH2 Suspected Human Carcinogen Anisidine (o & p) isomers NH2C6H4OCH3 Suspected Human Carcinogen Antimony compounds - as Sb Sb Suspected Human Carcinogen Arsenic and compounds except Arsine (as Confirmed Human Carcinogen As) As Arsine AsH3 Suspected Human Carcinogen Asbestos - all forms Confirmed Human Carcinogen Asphalt - petroleum fumes Suspected Human Carcinogen Benz(a)anthracene Suspected Human Carcinogen Benzene C6H6 Benzidine Confirmed Human Carcinogen Confirmed Human Carcinogen Benzo(b)flouranthene Suspected Human Carcinogen Benzo(a)pyrene Suspected Human Carcinogen Benzyl acetate Benzyl Chloride C6H5CH2CI Beryllium and compounds - as Be Be 1,3-Butadiene (Buta-1,3-diene) CH2=CHCH=CH2 tert-Butyl Chromate - as CrO3 Cadmium compounds Cd Calcium Chromate Captafol (ISO) C10H9Cl4NO2S Captan (ISO) C9H8Cl3NO2S Carbon Black C Carbon Tetrachloride CCl4 Chlordane (ISO) C10H6Cl8 Chlorinated Camphene (Toxaphene) Chlorodiphenyl (42% Chlorine) Chlorodiphenyl (54% Chlorine) Chloroform CHCl3 bis(Chloromethyl) ether Chloromethyl methyl ether beta-Chloroprene CH2=CClCH=CH2 Chromite Ore processing - as Cr Chromium IV compounds Chromyl Chloride Animal Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Animal Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Confirmed Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Confirmed Human Carcinogen Confirmed Human Carcinogen Suspected Human Carcinogen Chrysene Suspected Human Carcinogen Coal Tar pitch volatiles - as cyclohexane solubles Confirmed Human Carcinogen Cobalt metal - dust and fumes Co Crotonaldehyde CH3CH=CHCHO DDT (Dichlorodiphenyltrichloroethane) C14H9Cl5 Diazomethane CH2N2 Dichloroacetylene ClCCCl p-Dichlorobenzene C6H4Cl2 3,3'-Dichlorobenzidine Animal Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Animal Carcinogen Suspected Human Carcinogen 1,4-Dichloro-2-butene Suspected Human Carcinogen Dichloroethyl ether Suspected Human Carcinogen 1,3-Dichloropropene CHClCHCH2Cl Dieldrin (ISO) C12H6Cl6O Diglycidyl ether (DGE) (OCH2CHCH2)2O Dimethyl carbamoyl chloride Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen 1,1-Dimethyl hydrazine Suspected Human Carcinogen Dimethyl sulphate (CH3)2SO4 Dinitrotoluene CH3C6H3(NO2)2 Dioxane OCH2CH2OCH2CH2 Di-sec-octyl phthalate Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Epichlorohydrin OCH2CHCH2Cl Ethyl acrylate CH2=CHCOOC2H5 Suspected Human Carcinogen Suspected Human Carcinogen Ethyl bromide C2H5Br Ethylene dibromide BrCH2CH2Br Ethylene dichloride ClCH2CH2Cl Ethylene imine CH2CH2NH Ethylene oxide Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Formaldehyde Suspected Human Carcinogen Gasoline Suspected Human Carcinogen Heptachlor and heptachlor epoxide C10H5Cl7 Hexachlorobenzene - Skin Suspected Human Carcinogen Suspected Human Carcinogen Hexachlorobutadiene Suspected Human Carcinogen Hexachloroethane CCl3CCl3 Hexamethyl phosphoramide Suspected Human Carcinogen Suspected Human Carcinogen Hydrazine NH2NH2 Lead - inorganic dusts and fumes - as Pb Suspected Human Carcinogen Suspected Human Carcinogen Lead Chromate Suspected Human Carcinogen Lindane C6H5Cl6 Suspected Human Carcinogen Methoxychlor (ISO) C16H15Cl3O2 Suspected Human Carcinogen Methyl bromide - Skin CH3Br Suspected Human Carcinogen Methyl chloride CH3Cl Suspected Human Carcinogen Methylene chloride (Dichloromethane) CH2Cl2 Suspected Human Carcinogen 4,4'-Methylene bis(2-chloroaniline) (MOCA) Suspected Human Carcinogen 4,4'-Methylene dianiline H2NC6H4CH2C6H4NH2 Suspected Human Carcinogen Methyl hydrazine Suspected Human Carcinogen Methyl iodide CH3I beta-Naphthylamine Suspected Human Carcinogen Confirmed Human Carcinogen Nickel metal and insoluble compounds Confirmed Human Carcinogen Nickel, soluble compounds as Ni Confirmed Human Carcinogen p-Nitrochlorobenzene Suspected Human Carcinogen 4-Nitrodiphenyl Confirmed Human Carcinogen 2-Nitropropane CH3CH(NO2)CH3 N-Nitrosodimethylamine Suspected Human Carcinogen Suspected Human Carcinogen Oil mist, mildly refined cont. benzene Confirmed Human Carcinogen Pentachlorophenol C6Cl5OH Perchloroethylene (Tetrachloroethylene) CCl2=CCl2 N-Phenyl-beta-naphthylamine Suspected Human Carcinogen Animal Carcinogen Suspected Human Carcinogen o-Phenylenediamine C6H4(NH2)2 Phenylglycidylether (Phenyl-2,3epoxypropylether) C6H5OCH2CHCH2O Phenylhydrazine C6H5NHNH2 Propane sultone Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen beta-Propiolactone Suspected Human Carcinogen Propylene dichloride Suspected Human Carcinogen Propylene imine Suspected Human Carcinogen Propylene oxide Suspected Human Carcinogen Rosin, core solder pyro products formaldehyde Sensitiser, reduce exposure as much as possible Strontium chromate as Cr Styrene, monomer C6H5CHCH2 1,1,2,2-Tetrachloroethane Tetranitromethane o-Tolidine o-Toluidine p-Toluidine 1,1,2-Trichloroethane CH2ClCHCl2 T richloroethylene 1,2,3-Trichloropropane CH2ClCHClCH2Cl 2,4,6-Trinitrotoluene (TNT) CH3C6H2(NO2)3 Uranium, all compounds - as U U Vinyl acetate CH3COOCHCH2 Vinyl bromide CH2CHBr Vinyl chloride 4-Vinyl cyclohexene Vinyl cyclohexene dioxide C6H12O2 Vinylidene chloride Welding fumes Wood dust (certain hardwoods) Soft wood dusts Xylidene, mixed isomers Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Not Suspected as a Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Animal Carcinogen Suspected Human Carcinogen Confirmed Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen Suspected Human Carcinogen (CH3)2C6H3NH2 Zinc chromates Confirmed Human Carcinogen Occupational Exposure Limits - Control Limits Substance Acrylamide CH2=CHCONH2 TWA OEL- CL ppm TWA Short OEL-CL Term mg/m3 OEL-CL ppm Short 1995 Notes Term OEL-CL mg/m3 - 0.3 - - Sk Acrylonitrile CH2=CHCN Arsenic and compounds As 24 - 0.1 - Sk - except Arsine (as As) Asbestos - all forms See Asbestos Regulations Benzene C6H6 5 16 Bis-(chloromethyl) ether (BCME) ClCH2OCH2Cl 0.001 0.005 New Buta-1,3-diene CH2=CHCH=CH2 10 22 2-Butoxyethanol (EGBE) C4H9OCH2CH2OH 25 120 Sk Cadmium compounds except CdO fumes and CdS Cd Cadmium Oxide fumes CdO Cadmium Sulphide pigments (respirable dust Cd) CdS Carbon Disulphide CS2 10 0.05 0.05 0.04 30 - 0.05 Sk Chromium IV compounds 0.05 1,2 Dibromoethane (ethylene dibromide) BrCH2CH2Br Dichloromethane CH2Cl2 2,2'Dichloro-4,4'methylene dianiline (MbOCA) 0.5 100 4 350 0.005 Sk Sk CH3(C6H3ClNH2)2 2-Ethoxyethanol C2H5OCH2CH2OH 2-Ethoxyethyl acetate C2H5OCH2CH2OOCCH3 Ethylene oxide 10 37 10 54 5 10 Formaldehyde 2 Grain dust See Annexure 7 Hydrogen cyanide Isocyanate (all isomers) as NCO Lead and compounds- as Pb 2.5 10 0.02 2 10 2-Methoxyethanol CH3OCH2CH2OH 2-Methoxyethyl acetate CH3COOCH2CH2OCH3 Nickel Ni Nickel compounds as Ni Rubber process dust Rubber fume 5 16 5 24 0.05 0.1 0.5 8 0.6 Silica crystalline SiO2 Styrene C6H5CHCH2 1,1,1 -Trichloroethane CH3CCl3 T richloroethylene CCl2=CHCl Vinyl chloride CH2=CHCl 0.4 100 420 350 1900 100 535 7 250 450 150 Vinylidene chloride CH2=CCl2 Wood dust (hard wood) 10 40 5 Sk Sk 2.5 Sen 10 Sk 0.07 Sen See the Lead Regulations Sk Sk soluble insoluble See Annexure 6 1050 respirable dust 2450 802 Skin annual TWA OEL-CL of 3 ppm Sen Occupational Exposure Limits - Recommended Limits Substance Acetaldehyde CH3CHO Acetic acid CH3COOH Acetic anhydride (CH3CO)20 Acetone CH3COCH3 Acetonitrile CH3CN o-Acetyl Salicylic Acid (Aspirin) CH3COOC6H4COOH Acrolein (Acrylaldehyde) CH2=CHCHO Acrylic acid CH2=CHCOOH Aldrin (ISO) C12H8CL Allyl Alcohol CH2=CHCH2OH Allyl Chloride CH2=CHCH2Cl 1-Allyl-2,3-epoxypropyl ether CH2=CHCH2OCH2CHCH2O Allyl glycidyl ether (AGE) CH2CHCH2OCH2CHCH2O Aluminium - Alkyls Aluminium - Metal Dust Aluminium Oxides AbO3, Al(OH)3, AlOOH Aluminium - Soluble salts Aminodimethylbenzene (CH3)2C6H3NH2 2-Aminoethanol NH2CH2CH2OH 2-Aminopyridine NH2C5H4N Ammonia NH3 Ammonium Chloride - Fumes NH4Cl Ammonium Sulphamidate TWA TWA Short Short 1995 Notes OEL- OEL-RL Term Term RL mg/m3 OEL-RL OEL-RL ppm ppm mg/m3 100 180 150 270 10 25 15 37 - - 5 20 750 1780 1500 3560 40 70 60 105 -5 - - 0.1 0.25 0.3 0.8 10 30 - 0.25 25 13 5 22 20 4 2 10 60 0.75 10 6 44 Sk Sk Sk 5 22 10 44 Sk -2 10, 5 - - 10, 5 - -2 - 2 10 10 [total inhalable dust] {respirable dust} - [total inhalable dust] {respirable dust} - 50 Sk 3 8 6 15 0.5 2 25 17 - 10 2 35 - 8 24 20 10 20 nh2so3nh4 n-Amyl Acetate CH3COOC5H-n 100 530 150 800 sec-Amyl Acetate - - 150 800 CH3COOCH(CH3)C3H7 Aniline and homologues 2 10 5 20 Sk C6H5NH2 Anisidine (o & p) isomers 0.1 0.5 - - Sk NH2C6H4OCH3 Antimony compounds - as Sb - 0.5 - - Sb Arsine AsH3 0.05 0.2 - - Asphalt - petroleum fumes - 5 - 10 Asprin CH3COOC6H4COOH - 5 - 10 Atrazine (ISO) C8H4ClN5 - 10 - - Azinphos-methyl (ISO) - 0.2 0.6 - Sk (CH3O)2 PSSCH2 (C7 H4N3O) Azincine 0.5 1 - - Sk Aziridine CH2CH2NH - 10 - - y-BHC (ISO) C6H5Cl6 Barium soluble compounds as Ba Ba Barium Sulphate (respirable dust) BaSO4 Benomyl (ISO) C14H18N4O3 Benzenethiol C6H5SH Benzene-1,2,4-tricarboxylic acid 1,2 anhydride C9H4O5 p-Benzoquinone C6H4O2 Benzoyl Peroxide (C6H5CO)2O2 Benzyl butyl phthalate C6H5CH2COOC6H4COOC4H9 Benzyl Chloride C6H5CH2O Beryllium and compounds - as Be Be Biphenyl (C6H5)2 Bis (2,3-epoxypropyl) ether (OCH2CHCH2)2O Bis-(2-ethylhexyl) phthalate C6H4(COOCH2CH(C2H5)C4H9)2 2,2 Bis (p-methoxyphenyl)-1,1,1trichloroethane C16H15Cl3O2 Bismuth Telluride (Di-Bismuth TriTelluride) Bi2Te3 Bismuth Telluride - Se doped Bi2Te3 Bornan-2-one C10H16O Borates, tetra, Sodium salts Na2B4O7 - 0.5 - 1.5 Sk - 0.5 - - -2 - - - 10 0.5 2 - 0.04 - 15 - Sen 0.1 0.4 0.3 1.2 -5 - -5 - - 15 - - 0.002 - 0.2 1.5 0.6 0.1 0.6 - 4 - -5 - 10 - 10 - - -5 - 10 -2 12 - 1, 5, 3 - 10 18 - anhydrous (.IOH2O) (.5H2O) 1 decahydrate, pentahydrate Boron Oxide (Diboron Trioxide) B2O3 - 10 - 20 Boron Tribromide BBr3 - - 1 10 Boron Triflouride BF3 - - 13 Bromacil (ISO) C9H13BrN2O2 1 10 2 20 Bromine Br2 0.1 0.7 0.3 2 Bromine Pentaflouride BrF5 0.1 0.7 0.3 2 Bromochloromethane CH2BrCl 200 1050 250 1300 Bromoethane C2H5Br 200 890 250 1110 Bromoethylene CH2=CHBr 5 20 - - Bromoform CHBr3 0.5 5 - - Sk Bromomethane CH3Br 5 20 15 60 Sk Bromotriflouromethane CF3Br 1000 6100 12007300 Butane C4H10 Butan-1-ol C4H9OH 600 1430 750 1780 - - 50 150 Sk Butan-2-ol C3H6OHCH3 Butan-2-one CH3COC2H5 100 300 150 450 200 590 300 885 trans But-2-enal CH3CH=CHCHO 2 6 6 18 n-Butyl Acetate CH3COO(CH2)3CH3 150 710 200 950 sec-Butyl Acetate CH3COOCH(CH3)CH2CH3 200 950 250 1190 tert-Butyl Acetate CH3COOC(CH3)3 200 950 250 1190 n-Butyl Acrylate C7H12O2 10 55 - - n-Butyl Alcohol C4H9OH - - 50 150 Sk sec- Butyl Alcohol CH3CH2CHOHCH3 100 300 150 450 tert-Butyl Alcohol (CH3)3COH 100 300 150 450 n-Butylamine C4H9NH2 Butyl benzyl phthalate C6H5CH2COOC6H4COOC4H9 n-Butyl chloroformate ClCO2C4H10 - - 5 15 Sk -5-- 1 5.6 - - n-Butyl Glycidyl Ether (BGE) C4H9OCH2CHCH2O Butyl-2,3-epoxypropyl ether C4H9OCH2CHCH2O n-Butyl Lactate C7H14O3 2-sec-Butylphenol C2H5(CH3)CHC6H4OH 25 135 - 25 135 - 5 25 5 30 - - - Sk Caesium hydroxide CsOH Calcium Carbonate CaCO3 Calcium Cyanamide CaNCN Calcium Hydroxide Ca(OH)2 -2 -10,5 - - 0.5 -5 - - - total inhalable dust respirable dust 1 - Calcium Oxide CaO -2 - - Calcium Silicate - 10, 5 - - total inhalable dust respirable dust Camphor - synthetic C10H16O 2 12 3 18 Caprolactam dust NH(CH2)5CO -1 - 3 Caprolactam vapour NH(CH2)5CO 5 20 10 40 Captafol (ISO) C10H9Cl4NO2S - 0.1 - - Sk Captan (ISO) C9H8Cl3NO2S - 5 - 15 Carbaryl (ISO) C10H7OCONHCH3 - 5 - 10 Carbofuran (ISO) C12H15NO3 Carbon Black C Carbon Dioxide CO2 Carbon Monoxide CO - 0.1 - - - 3.5 - 7 5000 9000 1500027000 50 55 300 330 Carbon tetrabromide CBr4 0.1 1.4 0.3 4 Carbon Tetrachloride CCl4 2 12.6 - - Sk Carbonyl Chloride COCl2 - 0.4 - - Sk Catechol C6H4(OH)2 5 20 - - Cellulose - 10, 5 - 20 total inhalable dust respirable dust Cement - 10, 5 - - total inhalable dust respirable dust Chlordane (ISO) C10H6Cl8 Chlorinated biphenyls C12H7CI3 (approx) C6H2CI3C6H3CI2 - 0.5 - 2 Sk - 1, - 2, 1 42% Cl, 54% Cl 0.5 Chlorine Cl2 Chlorine Dioxide ClO2 Chlorine Triflouride ClF3 0.5 1.5 0.1 0.3 -- 1 0.3 0.1 3 0.9 0.4 Chloroacetaldehyde ClCH2CHO 2-Chloroacetophenone C6H5COCH2Cl Chloroacetyl Chloride ClCH2COCl -0.05 0.3 0.05 0.2 1 - - 3 - - Chlorobenzene C6H5Cl 50 230 - - Chlorobromomethane CH2BrCl 2-Chloro-1,3-butadiene CH2=CClCH=CH2 Chlorodiflouromethane CHClF2 200 1050 250 1300 10 36 - - Sk 1000 3500 - - 1 -Chloro-2,3-epoxypropane OCH2CHCH2Cl 2 8 5 20 Sk Chloroethane C2H5Cl 1000 2600 1250 3250 2-Chloroethanol ClCH2CH2OH -- 1 3 Sk Chloroethylene CH2=CHCl 7- - - Chloroform CHCl3 2 9.8 - - Sk Chloromethane CH3Cl 50 105 100 210 1 -Chloro-4-nitrobenzene ClC6H4NO2 - 1 - 2 Sk Chloropentaflouroethane CCIF2CF3 1000 6320 - - Chloropicrin CCl3NO2 0.1 0.7 0.3 2 beta-Chloroprene CH2=CClCH=CH2 10 36 - - Sk 3-Chloropropene CH2=CHCH2Cl 13 2 6 Chlorosulphonic acid HSO3Cl -1 - - alpha-Chlorotoluene C6H5CH2Cl 15 - - 2-Chlorotoluene C7H7Cl 50 250 - - 2-Cl-6-trichloromethyl pyridine C6H3Cl4N - 10 - 20 Chloropyrifos (ISO) C9H11Cl3NO3PS - 0.2 - 0.6 Sk Chromium Cr - 0.5 - - Chromium II compounds - as Cr Cr - 0.5 - - Chromium III compounds - as Cr Cr Coal Dust - 0.5 -2 - - Respirable dust Coal Tar pitch volatiles - as cyclohexane solubles - 0.14 - - Cobalt metal - dust and fumes Co - 0.1 - - Copper fumes Cu - 0.2 - - Copper dusts and mists - as Cu Cu - 1 - 2 Cotton Dust - raw - 0.5 - - See Annexure 4 Cresol - all isomers CH3C6H4OH Cristobalite, respirable dust SiO2 5 22 - - Sk Crotonaldehyde CH3CH=CHCHO 2 6 6 18 Cryofluorane (INN) CClF2CClF2 1000 7000 1250 8750 Cumene C6H5CH(CH3)2 Cyanamide H2NCN 25 120 -2 75 - 370 Sk - Cyanides - as CN -5 - - Sk Cyanogen (CN)2 10 20 - - Cyanogen Chloride ClCN - - 0.3 0.6 Cychlohexane C6H12 100 340 300 1030 Cyclohexanol C6H11OH 50 200 - - Sk Cyclohexanone C6H10O 25 100 100 400 Sk Cyclohexene C6H10 300 1015 - - Cyclohexylamine C6H11NH2 10 40 - - Sk Cyclonite (RDX) C3H6N6O6 - 1.5 - 3 Sk Cyhexatin (ISO) (C6H11)3SnOH - 5 - 10 2,4-D C6H3Cl2OCH2COOH - 10 - 20 DDM H2NC6H4CH2C6H4NH2 0.1 0.8 0.5 4 DDT (Dichlorodiphenyltrichloroethane) C14H9Cl5 1- DDVP (CH3O)2POOCHCCl2 0.1 1 - 2,4 DES C8H7Cl2NaO5S - 10 - 3 3 Sk 20 DMDT C16H15CI3O2 - 10 - - Derris, commercial C23H22O6 - 5 - 10 Diacetone Alcohol CH3COCH2C(CH3)2OH 50 240 75 360 Dialkyl 7-9 phthalate C6H4(COOC79H15-19)2 - 5- - Dialkyl phthalate C6H4(COOCH2CHCH)2 2,2'-Diaminodiethylamine (NH2CH2CH2)2NH - 5- 1 4 - - Sk 4,4'-Diaminodiphenylmethane (DADPM) 0.1 0.8 0.5 4 H2NC6H4CH2C6H4NH2 1,2-Diaminoethane NH2CH2CH2NH2 10 25 - - Diammonium peroxodisulphate (as S2O8) (NH4)2S2O8 Diatomaceous earth, respirable dust Diazinon - (ISO) C12H21N2O3PS - - 1- 1.5 0.1 - - 0.3 Sk Diazomethane CH2N2 0.2 0.4 - - Dibenzoyl peroxide (C6H5CO)2O2 Diborane B2H6 50.1 0.1 - - Dibrom 1,2-Dibromo-2,2dichloroethyldimethyl P C4H7Br2Cl2O4P 36 Dibromodiflouromethane CBr2F2 100 860 150 1290 Dibutyl Hydrogen Phosphate Di-n-butyl 1 phosphate (n-C4H9O)2(OH)PO 52 10 Dibutyl Phthalate C6H4(CO2C4H9)2 6,6'Di-tert-butyl-4,4'thiodi-m-cresol C22H30O2S - 510 - 10 20 Dichloroacetylene ClCCCl - - 0.1 0.4 1,2-Dichlorobenzene C6H4Cl2 - - 50 300 1,4-Dichlorobenzene C6H4Cl2 Dichlorobenzene 25 150 50 300 75 450 - - Dichloro diflouro methane CCl2F2 1000 4950 1250 6200 1,3-Dichloro 5,5-dimethyl hydantoin C5H6Cl2N2O2 - 0.2 - 0.4 Dichlorodiphenyltrichloroethane C14H9Cl5 - 1- 3 1,1-Dichloroethane CH3CHCl2 200 810 400 1620 1,2-Dichloroethane CH2ClCH2Cl 10 40 15 60 1.1- Dichloroethylene CH2CCI2 10 40 - - 1.2- DichIoroethyIene cis:trans isomers 60:40 ClCH=CHCI Dichloroflouromethane CHCl2F 200 790 250 1000 10 40 - - 2,4-Dichlorophenoxyacetic acid C6H3Cl2OCH2COOH - 10 - 20 1.3- Dichloropropene cis and trans 1 5 10 50 Sk isomers CHClCHCH2Cl Dichlorotetraflouroethane CClF2CClF2 1000 7000 1250 8750 Dichlorvos (ISO) (CH3O)2POOCH=CCl2 0.1 1 0.3 3 Sk Dicyclohexyl phthalate C6H4(COOC6H11)2 Dicyclopentadiene C10H12 Dicyclopentadienyl iron C10H10Fe - 5- 5 30 - 10 - - 20 Dieldrin (ISO) C12H8Cl6O - 0.25 - 0.75 Sk Diethanolamine HO(CH2)2NH(CH2)2OH 3 15 - - Diethylamine (C2H5)2NH 2-Diethylaminoethanol (C2H5)2NCH2CH2OH Diethylene glycol (HOCH2CH2)2O 10 30 25 75 10 50 - - Sk 23 100 - - Diethylamine triamine (NH2CH2CH2)2NH 1 4 - - Sk Diethyl ether C2H5OC2H5 400 1200 500 1500 Di-(2-ethylhexyl) phthalate (dioctyl phthalate) C6H4(COOCH2CH(C2H5)C4H9)2 - 5- 10 Diethyl ketone C2H5COC2H5 200 700 250 875 Diethyl phthalate C6H4(COOC2H5)2 - 5- 10 Diflourochloromethane CHClF2 Diglycidyl ether (DGE) (OCH2CHCH2)2O o-Dihydroxybenzene C6H4(OH)2 1000 3500 0.1 0.6 - 5 20 - - - m-Dihydroxybenzene C6H4(OH)2 p-Dihydroxybenzene C6H4(OH)2 10 45 20 90 - 2- 4 1,2-Dihydroxyethane CH2OHCH2OH - 10 - 60, particulate 125 vapour Diisobutyl ketone ((CH3)2CHCH2)2CO 25 150 - - Diisobutyl phthalate C6H4(COOCH2CH(CH3)2)2 - 5- - Diisodecyl phthalate (C10H21 CO2)2C6H4 - 5- - Diisononyl phthalate C6H4(COOC9H19)2 - 5- - Diisooctyl phthalate C6H4(CO2C8H17)2 Diisopropylamine (CH3)2CHNHCH(CH3)2 Diisopropyl ether (CH3)2CHOCH(CH3)2 - 5- - 5 20 - - Sk 250 1050 310 1320 Di-linear 79 phthalate C6H4(COOC7- 9H15-19)2 5- - Dimethoxymethane CH2(OCH3)2 1000 3100 1250 3880 N,N-Dimethyl acetamide CH3CON(CH3)2 10 36 20 71 Sk Dimethylamine (CH3)2NH 10 18 - - NN-Dimethylaniline C6H5N(CH3)2 5 25 10 50 Sk 1,3-Dimethylbutyl acetate CH3CO2CH(CH3)CH2CH-(CH3)2 50 300 100 600 NN-Dimethylethylamine C2H5(CH3)2N 10 30 15 45 Dimethylformamide HCON(CH3)2 2,6-Dimethylheptan-4-one ((CH3)2CHCH2)2CO 10 30 20 60 Sk 25 150 - - Dimethyl phthalate C6H4(COOCH3)2 - 5- 10 Dimethyl sulphate (CH3)2SO4 0.1 0.5 0.1 0.5 Sk Dinitolmide Dinitrobenzene all isomers C6H4(NO2)2 -5 0.15 1 -0.5 3 Sk Dinitro-o-cresol CH3C6H2(OH)(NO2)2 2,4-Dinitrotoluene CH3C6H3(NO2)2 - 0.2 1.5 - 0.6 Sk 5 Sk Dinonyl phthalate C6H4(COOC9H19)2 - 5- - Di-sec-octyl phthalate - 5 - 10 C6H4(COOCH2CH(C2H5)-C4H9)2 1,4-Dioxane, tech. grade OCH2CH2OCH2CH2 Dioxathion (ISO) C12H26O6P2S2 25 90 100 360 Sk - 0.2 - - Sk Diphenyl (C6H5)2 0.2 1.5 0.6 4 Diphenylamine (C6H5)2NH - 10 - 20 Diphenyl ether (vapour) C6H5OC6H5 17 - - Diphosphorus pentasulphide P2S5 Dipotassium peroxodisulphate as S2O8 K2S2O8 -1 -1 - 3 - Diquat dibromide (ISO) C12H1 2Br2N2 - 0.5 - Disodium disulphite Na2S2O5 -5 - Disodium peroxodisulphate (measured -1 as S2O8) Na2S2O8 - Disodium tetraborate Na2B4O7 (.10H2O) (.5H2O) - 1, 5, 1 1 - - anhydrous, decahydrate, pentahydrate Disulfoton (ISO) (C2H5O)2PSCH2CH2SC2H5 Disulphur dichloride S2Cl2 - 0.1 - 0.3 - 16 Disulphur decafluoride S2F10 0.025 0.25 0.0750.75 2,6-Di-tert-butyl-p-cresol (C4H9)2CH3C6H2OH - 10 - - Diuron (ISO) C9H10Cl2N2O Divanadium pentoxide (as V) V2O5 - 10 - 0.5, 0.05 Divinyl benzene C8H4(CHCH2)2 Dusts 10 50 -- - - total inhalable dust, fume & respirable dust - - see paragraph 36 of Annexure Emery Endosulfan (ISO) C9H6Cl6O3S Endrin (ISO) Ci2HsCl6O Enflurane CHFClCF2OCF2H Epichlorohydrin OCH2CHCH2Cl 1,2-Epoxy-4-epoxyethyl cyclohexane C6H12O2 2,3-Epoxypropyl isopropyl ether C3H7OCH2CHCH2O Ethane-1,2-diol CH2OHCH2OH Ethanethiol C2H5SH Ethanol C2H5OH - 10, 5 - - 0.1 - 0.1 20 150 28 10 60 5 - - total inhalable dust, respirable dust 0.3 Sk 0.3 Sk 20 Sk - 50 240 75 360 - 10, 60 - 1 25 particulate, vapour 0.5 1 2 10001900 - 3 - Ethanolamine NH2CH2CH2OH 3 8 500 1500 Ether C2H5OC2H5 Ethyl acetate CH3COOC2H5 400 1200 400 1400 - - Ethyl acrylate CH2=CHCOOC2H5 5 20 15 60 Sk Ethyl alcohol C2H5OH 10001900 - - Ethylamine C2H5NH2 Ethyl amyl ketone CH3CH2COCH2CH3CHCH2CH3 10 18 25 130 - - Ethyl benzene C6H5C2H5 100 435 125 545 Ethyl bromide C2H5Br 200 890 250 1110 Ethyl butyl ketone CH3CH2CO(CH2)3CH3 50 230 75 345 Ethyl chloride C2H5Cl 1000 2600 12503250 Ethyl chloroformate ClCO2C2H5 1 4.4 - - Ethylene Ethylene chlorohydrin ClCH2CH2OH - - 1 3 Sk Ethylenediamine NH2CH2CH2NH2 10 25 - - Ethylene dibromide BrCH2CH2Br 0.5 4 - - Sk Ethylene dichloride CH2CICH2Cl 10 40 15 60 Ethylene dinitrate CH2NO3CH2NO3 0.2 1.2 0.2 1.2 Sk Ethylene glycol CH2OHCH2OH - 10, - 1 25 particulate 60 vapour Ethylene glycol dinitrate (EGDN) CH2NO3CH2NO3 0.2 1.2 0.2 1.2 Sk Ethylene glycol monobutyl ether C4H9OCH2CH2OH 25 120 - - Sk Ethylene glycol monoethyl ether C2H5OCH2CH2OH 10 37 - - Sk Ethylene glycol monoethyl ether acetate 10 54 C2H5OCH2CH2OOCCH3 - - Sk Ethylene glycol monomethyl ether acetate CH3COOCH2CH2OCH3 5 24 - - Sk Ethylene glycol monomethyl ether CH3OCH2CH2OH 5 16 - - Sk Ethyleneimine CH2CH2NH 0.5 1 - - Sk Ethylene oxide CH2CH2O 5 10 - - Ethyl ether C2H5OC2H5 400 1200 500 1500 Ethyl formate HCOOC2H5 2-Ethylhexyl chloroformate CICO2(C2H5)CH2CH(CH2)3CH3 100 300 150 450 1 7.9 - - Ethylidene dichloride CH3CHCl2 200 810 400 1620 Ethyl mercaptan C2H5SH 0.5 1 23 4-Ethylmorpholine C6H13NO 5 23 20 95 Sk Ethyl silicate Si(OC2H5)4 10 85 30 255 Fenchlorphos (ISO) (CH3O)2PSOC6H2Cl3 Ferbam (ISO) ((CH3)2NCSS)3Fe Ferrocene C1oH1oFe Flourides as F F Flourine F2 Flourodichloromethane CHCl2F Flourotrichloromethane CCl3F Formamide HCONH2 Formic Acid HCOOH Furfural (2-Furaldehyde) C5H4O2 Furfuryl alcohol OCH=CHCH=CCH2OH - 10 - - - 10 - 20 - 10 - 20 - 2.5 - - - - 1 1.5 10 40 - - 1000 5600 1250 7000 20 30 30 45 59 - - 2 8 10 40 Sk 5 20 15 60 Sk Germanium tetrahydride (Germane) GeH4 Glutaraldehyde OCH(CH2)3CHO Glycerol mist CH2OHCHOHCH2OH Glycerol trinitrate CH2NO3CHNO3CH2NO3 Glycol monoethyl ether C2H5OCH2CH2OH Graphite C Guthion (CH3O)2PSSCH2(C7H4N3O) Gypsum CaSO4-2H2O 0.2 0.6 0.61.8 - - 0.20.7 - 10 - 0.2 2 0.2 2 Sk 10 37 0.2 2 Sk - 10, - - total inhalable dust, 5 respirable dust - 0.2 0.6 - Sk - 10, 5 - - total inhalable dust, respirable dust Halothane CHBrCI-CF3 10 80 - - y-HCH (ISO) CeH5Cl6 - 0.5 - 1.5 Sk Hafnium Hf - 0.5 - 1.5 Halothane CHBrClCF3 10 80 - - Heptachlor and heptachlor epoxide C10H5CI7 - 0.5 - 2 Sk n-Heptane C7H16 400 1600 500 2000 Heptan-2-one CH3(CH2)4COCH3 50 240 - - Heptan-3-one CH3CH2CO(CH2)3CH3 50 230 75 345 y-Hexachlorocyclohexane (y-HCH) - 0.5 - 1.5 Sk C6H5Cl6 Hexachloroethane CCI3CCI3 5 50, 10, 5 - vapour, total inhalable dust, respirable dust Hexahydro-1,3,5-trinitro-1,3,5-triazine - 1.5 - 3 Sk C3H6N6O6 Hexane isomers other than n-Hexane 500 1800 10003600 C6H14 n-Hexane C6H14 20 70 - - 1,6-Hexanolactam NH(CH2)5CO Hexan-2-one C3H9COCH3 Hexone (CH3)2CHCH2COCH3 Hexylene glycol (CH3)2COHCH2CHOHCH3 Hydrazine NH2NH2 Hydrazoic acid (as vapour) HN3 Hydrogen bromide HBr Hydrogen chloride HCl Hydrogen flouride (as F) HF Hydrogen peroxide H2O2 Hydrogen selenide (as Se) H2Se Hydrogen sulphide H 2S Hydroquinone C6H4(OH)2 4-Hydroxy-4-methyl-pentan-2-one CH3COCH2C(CH3)2OH 2-Hydroxypropyl acrylate CH2CHCOOCH2CHOHCH3 5 20, 1 5 20 50 205 25 125 10 40, 3 vapour, dust - - Sk 75 300 Sk 25 125 0.1 0.1 - - Sk - - 0.1 - - - 3 10 - - 57 - - 3 2.5 1 1.5 2 3 0.05 0.2 - - 10 14 15 21 - 2 -4 50 240 75 360 0.5 3 - - Sk 2,2'-Iminodiethanol HO(CH2)2NH(CH2)2OH 2,2'-Iminodi(ethylamine) (NH2CH2CH2)2NH ndene C9H8 ndium compounds - as In In Iodine I 2 odoform CHI3 Iodomethane CH3I ron Oxide fumes - as Fe Fe2O3 ron pentacarbonyl - as Fe Fe(CO)5 ron salts soluble - as Fe soamyl acetate CH3COOCH2CH2CH(CH3)2 soamyl alcohol (CH3)2CHCH2CH2OH soamyl ethyl ketone CH3COCH2CH2CH(CH3)2 sobutyl acetate CH3COOCH2CH(CH3)2 sobutyl alcohol (CH3)2CHCH2OH sobutyl methyl ketone (CH3)2CHCH2COCH 3 soflurane CF3CHClOCHF2 sooctyl alcohol (mixed isomers) C8H17OH sopentyl acetate CH3COOCH2CH2CH(CH3 2 sophorone C9H14O sophorone diisocyanate ( PD ) sopropyl acetate CH3COOCH(CH3)2 sopropyl alcohol (CH3)2CHOH sopropyl benzene C6H5CH(CH3)2 sopropyl chloroformate ClCO2CH(CH3)2 3 15 - - 1 4 - - Sk 10 45 15 70 - 0.1 - 0.3 - - 0.1 1 0.6 10 1 20 5 28 10 56 Sk - 5 - 10 0.01 0.08 -1 - - 2 100 525 125 655 100 360 125 450 50 240 75 360 150 700 187 875 50 150 75 225 50 205 75 300 Sk 50 380 - - 50 270 - - 100 525 125 655 - - 5 25 - 0.2 - 0.7 Sen - - 200 840 400 960 500 1225 Sk 25 120 75 370 1 5- - Isopropyl ether (CH3)2CHOCH(CH3)2 Isopropyl glycidyl ether (IGE) C3H7OCH2OCHCH2 250 1050 310 1320 50 240 75 360 Ketene CH2CO 0.5 0.9 1.5 3 Limestone - 10,5 - - total inhalable dust, respirable dust Lindane C6HsCl6 - 0.5 - 1.9 Sk Liquified pettroleum gas (LPG) 1000 1800 12502250 Mixture: C3H6 : C3H8 : C4H8 : C4H10 Lithium hydride LiH - 0.025 - - Lithium Hydroxide LiOH -- -1 MbOCA CH2(C6H3ClNH2)2 - 0.005 - - Sk MDA H2NC6H4CH2C6H4NH2 0.1 0.8 0.5 4 MDI - 0.02 - 0.07 Sen Magnesite 10, 5 - total inhalable dust, respirable dust Magnesium oxide (as Mg) MgO 5, 10 10 fume and respirable dust, respirable dust Malathion (ISO) C10H19O6PS2 - 10 - - Sk Maleic anhydride C4H2O3 0.25 1 -- Manganese dust and compounds Mn - 5 -- Manganese fumes Mn - 1 -3 Manganese cyclopentadienyl tricarbonyl - 0.1 - 0.3 Sk CsHCs-Mn(CO)3 Manganese tetroxide Mn3O4 - 1 -- Man made mineral fibre - - - See Annexure 3 Marble 10, 5 - Total inhalable dust, respirable dust Mequinol (INN) CH3OC6H4OH - 5 -- Mercaptoacetic acid C2H4O2S 1 5 -- Mercury - Alkyl compounds as Hg Hg - 0.01 - 0.03 Sk Mercury all other forms - as Hg Hg - 0.05 - 0.15 Mesityl oxide CH3COCH=C(CH3)2 15 60 25 100 Methacrylic acid CH2=C(CH3)COOH 20 70 40 140 Methacrylonitrile CH2=C(CH3)CN 1 3 - - Sk Methanethiol CH3SH 0.5 1 -- Methanol CH3OH 200 260 250 310 Sk Methomyl (ISO) CsH10N2O2S - 2.5 - - Sk Methoxychlor (ISO) C16H15Cl3O2 - 10 - - 1 -Methoxy propan-2-ol CH3OCH2CHOHCH3 100 360 300 1080Sk Methyl acetate CH3COOCH3 200 610 250 760 Methyl acrylate CH2=CHCOOCH3 10 35 - - Sk Methylal CH3(OCH3)2 1000 3100 12503880 Methylal alcohol CH3OH 200 260 250 310 Sk Methylamine CH3NH2 10 12 - - Methyl n-amyl ketone CH3(CH2)4COCH3 50 240 - - N-Methyl aniline C6H5NHCH3 0.5 2 - - Sk Methyl bromide - Skin CH3Br 5 20 15 60 Sk 3-Methylbutan-1-ol (CH3)2CHCH2CH2OH 100 360 125 450 1 -Methylbutyl acetate - - 150 800 CH3COOCH(CH3)C3H7 Methyl n-butyl ketone CH3(CH2)3COCH3 5 20 - - Sk Methyl chloride CH 3Cl 50 105 100 210 Methyl chloroform CH3CCl3 350 1900 450 2450 Methyl 2-cyanoacrylate 2 8 4 16 CH2=C(CN)COOCH3 Methylcyclohexane C7H14 400 1600 500 2000 Methylcyclohexanol CH3C6H10OH 50 235 75 350 Sk 2-Methylcyclohexanone 50 230 75 345 Sk CH3CHCO(CH2)3CH2 Methylcyclopentadienyl manganese tricarbonyl (as Mn) - 0.1 - 0.6 2-Methyl-4,6-dinitrophenol CH3C6H2(OH)(NO2)2 - 0.2 - 0.6 Sk 4,4'-Methylene bis(2chloroaniline) (MbOCA) CH2(C6H3ClNH2)2 Methylene chloride (Dichloromethane) - 0.005 - - Sk 100 350 250 780 CH2O2 4,4'-Methylene-diphenyl diisocyanate (MDI) - 0.02 - 0.07 Sen 4,4'-Methylenedianiline (MDA) 0.1 0.8 0.5 4 H2NC6H4CH2C6H4NH2 Methyl ethyl ketone (MEK) CH3COC2H5 200 590 300 885 Methyl ethyl ketone peroxides C8H16O4 - - 0.2 1.5 or C8H18O6 Methyl formate HCOOCH3 100 250 150 375 5-Methyl heptan-3-one 25 130 - - CH3CH2COCH2CH3CHCH2CH3 5-Methyl hexan-2-one 50 240 75 360 CH3COCH2CH2CH(CH3)2 Methyl hydrazine 0.2 0.35 0.2 0.35 Sk Methyl iodide CH3I 5 28 10 56 Sk Methyl isoamyl ketone CH3COCH2CH2CH(CH3)2 Methyl isobutyl carbinol CH3CHOHCH2CH(CH3)2 Methyl isobutyl ketone (MIBK) (CH3)2CHCH2COCH3 Methyl isocyanate Methyl mercaptan CH 3SH Methyl methacrylate CH2=C(CH3)COOCH3 50 240 75 360 25 100 40 160 Sk 50 205 75 300 Sk - 0.02 - 0.07 Sen 0.5 1 -- 100 410 125 510 Methyl parathion C8H10NO5PS 2-Methylpentane-2,4-diol (ch3)2cohch2ch)hch3 - 0.2 - 0.6 Sk 25 125 25 125 4-Methylpentan-2-ol CH3CHOHCH2CH(CH3)2 4-Methylpentan-2-one (CH3)2CHCH2COCH3 4-Methylpent-3-and-2-one CH3COCH=C(CH3)2 4-Methyl-m-phenylene diisocyanate 2-Methylpropan-1 -ol (CH3)2CHCH2OH 2-Methylpropan-2-ol (CH3)3COH Methyl propyl ketone CH3COC3H7 1 -Methyl-2-pyrrolidone CH3N(CH2)3CO Methyl silicate (CH3O)4Si alpha Methyl styrene C6H5C(CH3)=CH2 Methyl styrene (all isomers) CH3C6H4CH = CH2 n-Methyl-n,2,4,6-tetranitro aniline (NO2)3C6H2N(NO2)CH3 25 100 40 160 Sk 50 205 75 300 Sk 15 60 25 100 - 0.02 - 0.07 Sen 50 150 75 225 100 300 150 450 200 700 250 875 100 400 - 1 6 5 30 - - 100 480 100 480 150 720 - 1.5 - 3 Sk Mevinphos (ISO) C7H13O6P Mica Molybdenum, soluble compounds as Mo 0.01 0.1 0.03 0.3 Sk 10, 1 - total inhalable dust, respirable dust - 5 - 10 Molybdenum, insoluble compounds, as - 10 - 20 Mo Monochloroacetic acid ClCH2CO2H 0.3 1 - - Sk Morpholine C4H9NO 20 70 30 105 Sk Naled (ISO) C4H7Br2Cl2O4P Naphthalene C1oH8 1,5-Napthylene diisocyanate Nickel carbonyl Ni(CO)4 -3 - 6 Sk 10 50 15 75 - 0.02 - 0.07 Sen -- 0.1 0.24 Nickel, organic compounds (as Ni) Nicotine C1oH14N2 Nitrapyrin C6H3Cl4N Nitric acid HNO3 Nitric oxide NO 4-Nitroaniline NO2C6H4NH2 Nitrobenzene C6H5NO2 Nitroethane C2H5NO2 Nitrogen dioxide NO2 Nitrogen monoxide NO Nitrogen triflouride NF3 Nitroglycerin CH2NO2CHNO3CH2NO3 Nitromethane CH3NO2 1-Nitropropane C3H7NO2 2-Nitropropane CH3CH(NO2)CH3 Nitrotoluene (all isomers) CH3C6H4NO2 Nitrous oxide N2O -1 -3 - 0.5 - 1.5 Sk - 10 - 20 2 5 4 10 25 30 35 45 -6- - Sk 1 5 2 10 Sk 100 310 - - 3559 25 30 35 45 10 30 15 45 0.2 2 0.2 2 Sk 100 250 150 375 25 90 - - 10 36 20 72 5 30 10 60 Sk 100 180 - - Octachloronaphthalene C10Cls n-Octane CH3(CH2)6CH3 Orthophosphoric acid H3PO4 Osmium tetroxide - as Os OsO4 Oxalic acid COOHCOOH Oxalonitrile (CN)2 2,2'-Oxydiethanol (HOCH2CH2)2O Ozone O3 300 0.0002 10 23 0.1 0.1 1450 1 0.002 1 20 100 0.2 375 0.0006 0.3 0.3 Sk 1800 3 0.006 2 0.6 PCB's - -- - see chlorinated biphenyls Paraffin wax fumes - 2- 6 Paraquat dichloride (CH3(CsH4N+)2CH3)-(Cl-2) - 0.1 - - Respirable dust Parathion (ISO) (C2H5O)2PSOC6H4NO2 - 0.1 - 0.3 Sk Parathion-methyl (ISO) C8H10NO5PS - 0.2 - 0.6 Sk Pentacarbonyliron (as Fe) Fe(CO)s 0.01 0.08 - - Pentachlorophenol C6Cl5OH - 0.5 - 1.5 Sk Pentaerythritol C(CH2OH)4 - 10, 5 - 20 total inhalable dust, respirable dust Pentane C5H-12 600 1800 750 2250 2-Pentanone, 3-Pentanone CH3COC2H7 200 700 250 875 Pentyl acetate CH3COOC5Hn 100 530 150 800 Perchloroethylene 50 335 150 1000 (Tetrachloroethylene) CCl2=CCl2 Perchloryl flouride ClO3F Phenacyl chloride C6H5COCH2Cl Phenol C6H5OH p-Phenylenediamine C6H4(NH2)2 Phenyl-2,3-epoxypropyl ether C6H5OCH2CHCH2O Phenylethylene C6H5CH=CH2 Phenylhydrazine C6H5NHNH2 2-Phenylpropene C6H5C(CH3)=CH2 Phorate (ISO) C7H17O2PS3 Phosdrin C7H13O6P Phosgene COCl2 Phosphine PH3 Phosphorus (yellow) P4 Phosphorus pentachloride PCl5 Phosphorus pentasulphide P2S5 Phosphorus trichloride PCl3 Phosphoryl trichloride POCl3 Phthallic anhydride C6H4(CO2)O Picloram (ISO) C6H3Cl3N2O2 Picric acid HOC6H2(NO2)3 Piperazine dihydrochloride C4H10N2.2HCl Piperidine C5H11N Plaster of Paris (Calcium sulphate) (CaSO4)2H2O Platinum metal Pt Platinum, soluble salts - as Pt Pt Polychlorinated biphenyls Polyvinyl chloride (PVC) Portland cement Potassium hydroxide KOH Propane-1,2-diol CH3CHOHCH2OH n-Propanol CH3CH2CH2OH Propan-1 -ol CH3CH2CH2OH Propan-2-ol (CH3)2CHOH Propargyl alcohol HCCCH2OH Propionic acid CH3CH2COOH Propoxur (ISO) 3 0.05 5 1 14 0.3 19 0.1 6 6 28 -10 38 Sk - - Sk -- 100 420 250 1050 5 20 10 45 Sk - - 100 480 - 0.05 - 0.2 Sk 0.01 0.1 0.03 0.3 Sk 0.1 0.4 - - - - 0.3 0.4 - 0.1 - 0.3 0.1 1 -- -1 -3 0.2 1.5 0.5 3 0.2 1.2 0.6 3.6 1 6 4 24 Sen - 10 - 20 - 0.1 - 0.3 Sk - 5 -- 1 3.5 - 10, 5 - - Sk - total inhalable dust, respirable dust -5 - 0.002 -- - - Sen - See chlorinated biphenyls - 10, 5 - - total inhalable dust, respirable dust - 10, 5 - - total inhalable dust, respirable dust -- 150 470, 10 - 2 - vapour + particulates particulates 200 500 250 625 Sk 200 500 250 625 Sk 400 980 500 1225Sk 1 2 3 6 Sk 10 30 15 45 - 0.5 - 2 HsCNHCOOCel-UOCI-KCHsh n-Propyl acetate CH3COOC3H7 Propylene dinitrate CH2NO3CHNO3CH3 Propylene glycol CH3CHOHCH2OH Propylene glycol dinitrate CH2NO3CHNO3CH3 Propylene glycol monomethyl ether CH3OCH2CHOHCH3 Prop-2-yn-1 -ol HC=CCH2OH Pulverised Fuel Ash Pyrethrum (Pyrethrins) (ISO) Pyridine C5H5N 2-Pyridylamine NH2C5H4N Pyrocatechol C6H4(OH)2 200 840250 1050 0.2 1.2 0.2 1.2 Sk - - - - See Propane-1,2-diol above - - - - See Propylene dinitrate above 100 360 3001080Sk 1 2 3 6 Sk 10, 5 - - total inhalable dust, respirable dust 5 - 10 5 15 10 30 0.5 2 28 5 20 Quartz, crystalline SiO2 Quinone C6H4O2 - 0.4 - - respirable dust 0.1 0.4 0.3 1.2 RDX C3H6N6O8 Resorcinol C6H4(OH)2 Rhodium metal and insoluble compounds - as Rh Rh - 1.5 - 3 Sk 10 45 20 90 - 0.1 - 0.3 metal fumes and dust Rhodium, soluble compounds as Rh Rh - 0.001 - 0.003 soluble salts Ronnel (CH3O)2PSOC6H2Cl3 10 Rosin, core solder pyro products formaldehyde 0.1 0.3 Sen Rotenone (commercial) (ISO) C23H22O6 Rouge 5 10, 5 10 total inhalable dust, respirable dust Selenium and compounds - as Se Se Silane SiH4 Silica, amourphous SiO2 - 0.1 0.5 0.7 - 6, 3 - 1 - Silica, fused SiO2 Silicon Si - 0.1 - - 10,5 - Silicon carbide SiC - 10,5 - 1.5 total inhalable dust, respirable dust respirable dust Total inhalable dust, respirable dust Total inhalable dust, respirable dust Silicon tetrahydride - Silane SiH4 0.5 0.7 1 1.5 Silver metal Ag - 0.1 - - Silver, soluble compounds - as Ag Ag - 0.01 - - Sodium azide NaN3 - - - 0.3 Sodium 2,4-dichlorophenoxyethyl - 10 - 20 sulphate C8H7Cl2NaO3S Sodium flouroacetate CH2FCOONa - 0.05 - 0.15 Sk Sodium hydrogen sulphite NaHSO3 -5- - Sodium hydroxide NaOH - - -2 Sodium metabisulphite Na2S2O5 - 5 - - Starch - 10, 5 - - total inhalable dust, respirable dust Stibine SbH3 0.1 0.5 0.3 1.5 Strychnine C21H22N2O3 - 0.15 - 0.45 Styrene, monomer C6H5CHCH2 100 420 250 1050 Subtilisins (proteolytic enzymes) - 0.00006 - 0.00008 Sucrose C12H22O11 - 10 - 20 Sulfotep (ISO) (C2H5)4P2S2O5 - 0.2 - - Sk Sulphur dioxide SO2 2 5 5 15 Sulphur hexaflouride SF6 1000 6000 1250 7500 Sulphuric acid H2SO4 -1 -- Sulphur monochloride S2Cl2 - -16 Sulphur pentachloride S2F10 0.025 0.25 0.075 0.75 Sulphur tetraflouride SF4 0.1 0.4 0.3 1 Sulphuryl flouride (Sulphuryl diflouride) SO2F2 5 20 10 40 2,4,5-T (ISO) C8H5Cl3O3 TDI TEDP (Tetraethyl dithiopyrophosphate) (C2H5)4P2S2O5 TEPP (ISO) (Tetraethyl pyrophosphate) (C2H5)4P2O7 Talc (containing no asbestos fibers) Tantalum metal and oxide dusts - as Ta Ta Tellurium and compounds - as Te Te - 10 - 20 - 0.02 - 0.07 Sen - 0.2 - - Sk 0.004 0.05 0.01 0.2 Sk - 10, 1 - 5- - total inhalable dust, respirable dust 10 - 0.1 - - except Hydrogen Telluride Terphenyls, all isomers C18H14 - - 0.5 5 1.1.2.2- Tetrabromoethane CHBr2CHBr2 0.5 7 - - Sk Tetrabromomethane CBr4 0.1 1.4 0.3 4 Tetracarbonylnickel (as Ni) Ni(CO)4 - - 0.1 0.24 1.1.1.2- Tetrachloro-2,2-diflouroethane CCl3CClF2 100 834 100 834 1.1.2.2- Tetrachloro-1,2-diflouroethane CCl2FCCl2F 100 834 100 834 Tetrachloroethene CCl2CCl2 50 335 150 1000 Tetrachloromethane CCI4 2 12.6 - - Sk Tetrachloronaphthalene, all isomers - 2-4 C10H4Cl4 O,O,O',O'-Tetraethyl dithiopyrophosphate - 0.2 - - Sk (C2H5)4P2S2O5 O,O,O',O'-Tetraethyl pyrophosphate 0.004 0.05 0.01 0.2 Sk (C2H5)4P2O7 Tetraethyl orthosilicate Si(OC2H5)4 10 85 30 255 Tetraflourodichloroethane CClF2CClF2 1000 700012508750 Tetrahydrofuran (C2H4)2O 200 590 250 735 Tetramethyl orthosilicate (CH3O)4Si 1 6 5 30 Tetramethyl succinonitrile C8H12N2 0.5 3 2 9 Sk Tetrasodium pyrophosphate Na4P2O7 - 5 - - Sk Tetryl (NO2)3C6H2N(NO2)CH3 - 1.5 - 3 Sk Thallium, soluble compounds Tl - 0.1 - - Sk 4,4'-Thio bis(6-tert butyl-m-cresol) C22H30O2S Thioglycolic acid C2H4O2S - 10 - 20 1 5- - Thionyl chloride SOCl2 - -15 Thiram (ISO) (CH3)2NCS2CS2N(CH3)2 Tin, oxide and inorganics except SnH4 Sn Tin, organic compounds as Sn except Cyhexatin Sn - 5 - 10 - 2-4 - 0.1 - 0.2 Sk Titanium dioxide TiO2 - 10, 5 - - total inhalable dust, respirable dust Toluene C6H5CH3 50 188 150 560 Sk Toluene, 2,4 diisocyanate (TDI) - 0.02 - 0.07 Sen p-Toluenesulphonyl chloride ch3c6h4so2ci 1,4,7-Tri-(aza)-heptane (NH2CH2CH2)2OH 1 - -5 4- - Sk Tribromomethane CHBr3 0.5 5 - - Sk Tributyl phosphate, all isomers - 5-5 (C4H9)3PO4 Tricarbonyl (eta-cyclopentadienyl) 0.1 0.3 Sk manganese (as Mn) (C5H5)-Mn(CO)3 Tricarbonyl (methylcyclopentadienyl) manganese (as Mn) (CH3)C5H4)Mn(CO)3 - 0.2 - 0.6 Sk Trichloroacetic acid CCl3COOH 15 1.2.4- Trichlorobenzene C6H3Cl3 5 40 5 40 1.1.1- Trichlorobis (chlorophenyl) ethane - 1 - 3 Cl4H9Cl5 1.1.2- Trichloroethane CH2ClCHCl2 10 45 20 90 Sk Trichloroflouromethane CClF3 1000 560012507000 Trichloromethane CHCl3 2 9.8 - - Trichloronitromethane CCl3NO2 0.1 0.7 0.3 2 2.4.5- Trichlorophenoxy acetic acid - 10 - 20 C8H5Cl3O3 1.2.3- Trichloropropane CH2ClCHClCH2Cl 50 300 75 450 Sk 1,1,2-Trichloro-1,2,2-triflouroethane CCl2FCClF2 1000 760012509500 Tri-o-Cresyl phosphate (CH3C6H4O)3PO - 0.1 - 0.3 Tricyclohexyl tin hydroxide (C6Hn)3SnOH - 5 - 10 Tridymite SiO2 - 0.4 - - respirable dust Triethylamine (C2H5)3N 10 40 15 60 Triflourobromomethane CF3Br 1000 610012007300 Trimanganese tetraoxide Mn3O - 1- - Trimellitic anhydride C9H4O5 - 0.04 - - Sen Trimethylamine (CH3)3N 10 24 15 36 Trimethylbenzene all isomers and mixtures C6H3(CH3)3 25 123 - 3.5.5- Trimethylcyclohex-2-enone C9H14O - - 5 25 Trimethyl phosphite (CH3O)3P 2 10 - - 2.4.6- Trinitrophenol HOC6H2(NO2)3 - 0.1 - 0.3 Sk 2.4.6- Trinitrotoluene (TNT) - 0.5 - - Sk CH3C6H2(NO2)3 Triphenyl phosphate (C6H5)3PO4 - 3-6 Tripoli, respirable dust SiO2 - 0.4 - - Tri-o-tolyl phosphate (CH3C6H4O)3PO - 0.1 - 0.3 Tungsten, insoluble compounds - as W W - 5 - 10 Tungsten, soluble compounds - as W W - 1 - 3 Turpentine C10H16 100 560 150 840 Uranium, all compounds - as U U - 0.2 - 0.6 Vanadium pentoxide V2O5 Vinyl acetate - 0.5, 0.05 10 30 - total inhable, fume and respirable dust 20 60 CH3COOCHCH2 Vinyl benzene C6H5CH=CH2 100 420 2501050 Vinyl bromide CH2CHBr 5 20 Vinyl chloride 5 15 4-Vinyl cyclohexene 0.1 0.4 Vinyl cyclohexene dioxide C6H12O2 10 60 Vinyl toluene CeHsC(CH3)CH2 - - 100 480 Warfarin (ISO) C19H16O4 White spirit - 0.1 - 0.3 100 575 125 720 Xylene, all and mixed isomers C6H4(CH3) Xylidene, mixed isomers (CH3)2C6H3NH2 100 435 150 650 Sk 2 10 10 50 Sk Yttrium, as metal and compounds Y -1-3 Zinc chloride fumes ZnCl2 Zinc di-stearate Zn(C18H3sO2)2 Zinc oxide fumes ZnO Zirconium and compounds - as Zr Zr -1 - 10, 5 -5 -5 -2 -20total inhalable dust, respirable dust -10 -10 Annexure 2 Calculation of exposure with regard to the specified reference periods This Annexure reproduces the approved method for the calculation of exposure in relation to the 8-hour, short-term and one-year reference periods. 1. The 8-hour reference period 1.1. The term '8-hour reference period' relates to the procedure whereby the occupational exposures in any 24-hour period are treated as equivalent to a single uniform exposure for 8 hours [the 8-hour time weighted average (TWA) exposure]. 1.2. The 8-hour TWA may be represented mathematically by: c^ + c2t2+..+c^ 8 where C(1) is the occupational exposure value (concentration) and T(1) is the associated exposure time in hours in any 24-hour period. Examples (a) The operator works for 7h20 min. on a process in which he is exposed to a substance hazardous to health. The average exposure during that period is measured as 0.12 mg/m3. The 8- hour TWA therefore is- 7h20min (7.33h) at 0.12mg/m3 40 min (0.67h) at Orng/m3 TT1hat .is- 4[-0-.-1--2---x-7--.-3-3L)--+1-(-0--x--0--.-6--7L) 8 = 0.11 mg/m3 (b) The operator works for eight hours on a process in which he is exposed to a substance hazardous to health. The average exposure during that period is measured as 0,15mg/m3. The 8-hour TWA therefore is 0.15 *8 8 = 0.15 mg/m3 (c) Working periods may be split into several sessions for the purpose of sampling to take account of rest and meal breaks, etc. This is illustrated by the following example: Exposure is assumed to be zero during the period 10:30 to 10:45, 12:45 to 13:30 and 15:30 to 15:45. Working period 08:00- 10:30 Exposure {mg/m3) 0.32 Duration of sampling (h) 2.5 10:45 - 12:45 13:30 -1 5:30 15:45 - 17:15 0.07 0.20 0.10 2 2 1.5 The 8-hour TWA therefore is - (0.32 x 2.5) + (0.07 x 2) + (0.20 * 2) + (0.10 * 1.5) + (0 *1.25) = 0.19 mg/m3 8 (d) An operator works for eight hours during the night shift on a process in which he is intermittently exposed to a substance hazardous to health. The operators work pattern during the working period should be known and the best available data relating to each period of exposure should be applied in calculating the 8-hour TWA. This data should be based on direct measurement, estimates based on data already available or reasonable assumptions. Working period Task 22:00 24:00 Helping in workshop 24:00 01:00 Cleaning elsewhere in factory 1.00 -04:00 Working in canteen 04:00 06:00 Cleaning up after breakdown in workshop The 8-hour TWA therefore is - (0.10 *2) +(0.21 x 2) + (0 x 4) 8 = 0.78 mg/m3 Exposure (mg/m3) 1. 10 (known to be the exposure of full-time group in the workshop) 0 (assumed) 0 (assumed) 0.21 (assumed) 2. The short-term reference period Exposure should be recorded as the average over the specified short-term reference period and should normally be determined by sampling over that period. Example where the short-term reference period is 15 minutes (a) Exposure period is less than 15 minutes: The sampling result should be averaged over 15 minutes. For example, if a 5minute sample produces a level of 600 ppm and is immediately followed by a period of zero exposure, then the 15-minute average exposure will be 200 ppm: (b) Exposure period is 15 minutes or longer Measurements should be taken over a 15-minute period and the result is the 15-minute average exposure. Measurements for periods greater than 15 minutes should not be used to calculate a 15-minute average exposure, but if the average exposure over the longer period exceeds the 15-minute exposure limit, then this limit must have been exceeded over some 1 5-minute period. 3. The one-year reference period for vinyl chloride Exposure should be recorded as the time-weighted average of vinyl chloride in the atmosphere of a work-ing area over a period of one year. At enclosed vinyl chloride polymerisation plants, continuous or permanent sequential sampling methods must be used. Where discontinuous measurements are made, the frequ ency of measurements and the number per year should be such that it is possible to state with a statistical confidence coefficient of at least 95% that the true mean annual concentration did not exceed the annual maximum exposure limit. Only periods of plant operation including, where necessary, maintenance time should be taken into account. Annexure 3 Methods of measurement and calculation for determining fibre concentrations of manmade mineral fibre 1. The method must determine the exposure of employees by sampling in the breathing zone of the employee exposed. 2. 'Fibre' means a particle with a length > 5 ^m, an average diameter < 3 ^m, and a ratio of length to diameter > 3 to 1, which can be seen using the system specified in paragraph 3. 3. Fibres shall be counted in accordance with AIA RTM1. 4. The results shall be regularly tested by quality assurance procedures to ensure that the results are in satisfactory agreement with the average of results, obtained by approved inspection authorities (AIA) participating in a national quality assurance scheme, using the method specified in paragraphs 1 to 3 above. Annexure 4 Cotton Dust 1. The OEL for cotton dust is 0.5 mg/m3 total dust less fly, 8-hour TWA. This figures is not a personal exposure limit but a background air standard determined by using static samplers. This OEL-RL applies to dust from the processing and handling of raw and waste cotton, including blends containing raw or waste cotton, with the following exceptions: (a) dust from weaving, knitting, braiding and subsequent processes; and (b) dust from bleached or dyed cotton. 2. Under the HCS Regulations, assessors must satisfy themselves that the assessment takes account of people who work intensively with the material e.g. at bale opening, waste handling, maintenance of dust extraction equipment and cleaning procedures, and who are therefore likely to be exposed to dust. 3. Where the OEL-RL does not apply, exposure should be kept below both 10 mg/m3 8-hour TWA total inhalable dust and 5 mg/m3 8-hour TWA respirable dust, determined by a personal sampling method. Annexure 5 Asphyxiants 1. Some gases and vapours, when present at high concentration in air, act as simple asphyxiants by reducing the oxygen content by dilution to such an extent that life cannot be supported. Many asphyxiants are odourless, colourless and not readily detectable. Monitoring the oxygen content of the air is often the best means of ensuring safety. The oxygen content of air in the workplace should never be allowed to fall below a minimum of 18% by volume under normal atmospheric pressure. Particular care is necessary when dense asphyxiants, e.g. argon, are used, since very high localised concentrations can arise owing to their collecting in pits, confined spaces and other low-lying areas where ventilation is likely to be poor. 2. Many asphyxiants present a fire or explosion risk. The concentration at which these risks can arise are liable to be well below those levels at which asphyxiation is likely to occur and should be taken into account when assessing the hazards. 3. Although asphyxiants are listed in Table 2 of Annexure 1, they are not substances hazardous to health for the purpose of the HCS Regulations. Annexure 6 Rubber fume and rubber process dust 1. Rubber fume is fume evolved in the mixing, milling and blending of natural rubber or synthetic elastomers, or of natural rubber and synthetic polymers combined with chemicals, and in the processes which convert the resultant blends into finished products or parts thereof, and including any inspection procedures where fume continues to be evolved. 2. The limit relates to cyclohexane soluble material determined by the method described in 'Rubber fume in air, measured as total particulates and cyclohexane soluble material'. 3. Rubber process dust is evolved during the manufacture of intermediates or articles from natural rubber and/or synthetic elastomers. This definition does not include dusts, which, for occupational purposes, can be dealt with individually. In each case the relevant OEL will apply. Otherwise, where a substance with an OEL is present in a mixed dust, the OEL for that substance will apply, in addition to the rubber process dust limit. 4. Methods for personal sampling and measurement of total inhalable dusts are available in 'General method for the gravimetric determination of respirable and total inhalable dust' and 'Rubber fume in air measures as total particulates and cyclohexane soluble material'. Annexure 7 The definition of Grain Dust 1. Grain dust is taken to be dust arising from the harvesting, drying, handling, storage or processing of barley, wheat, oats, maize and rye, including contaminants. Acknowledgement to HER BRITANNIC MAJESTY'S STATIONERY OFFICE The Department of Labour hereby acknowledges the permission given by the Controller of HER BRITANNIC MAJESTY'S STATIONERY OFFICE (HMSO) for the reproduction of the Crown Copyright material listed below, or part thereof. The conditions under which this permission was granted, are subject to the following; The source of the material must be acknowledged; and It must be mentioned that permission for the reproduction of such material was given by the Controller of HMSO. List of material 1. Guidance note S20 2. HS(G)61 3. MDHS 14 4. MDHS 47 5. INDG(G)64-L 6. COSSH assessments 7. Pesticides: Code of Practice 8. EH14 9 EH22 10 EH23 11 EH25 12 EH28 13 EH40 14 EH42 15 EH44 16 EH56 Annexure 8 Material safety data sheet MATERIAL SAFETY DATA SHEET No: Date issued: Page of Name: COMPANY DETAILS Emergency telephone no.: Address: Telex: Tel: Fax: 1) Product and Company Identification: (Page 1 may be used as an emergency safety data sheet) Trade name : Chemical abstract no. : Chemical family : Chemical name: NIOSH no.: Hazchem code: Synonyms: 2) Composition Hazardous components: UN no.: EEC classification: R Phrases: 3) Hazards Identification Main hazard: Flammability: Chemical hazard Biological hazard: Reproductive hazard: Eye effects: eyes: Health effects - skin: Health effects - ingestion: Health effects - inhalation: Carcinogenicity: Mutagenicity: Neurotoxicity: 4) First-aid Measures Product in eye: Product on skin: Product ingested: Product inhaled: 5) Fire-fighting Measures Extinguishing media: Special hazards: Protective clothing: 6) Accidental Release Measures Personal precautions: Environmental precautions: Small spills: Large spills: 7) Handling and Storage Suitable material: Handling/storage precautions: 8) Exposure Control/Personal Protection Occupational exposure limits: Engineering control measures: Personal protection - respiratory: Personal protection - hand: Personal protection - eye: Personal protection - skin: Other protection: 9) Physical and Chemical Properties Appearance: Odour: pH: Boiling point: Melting point: Flash point: Flammability: Auto flammability: Explosive properties: Oxidizing properties: Vapour pressure: Density: Solubility - water: Solubility - solvent: Solubility - coefficient 10) Stability and Reactivity Conditions to avoid: Incompatible materials: Hazardous decomposition products: 11) Toxicological Information Acute toxicity: Skin and eye contact: Chronic toxicity: Carcinogenicity: Mutagenicity: Neurotoxicity: Reproductive hazards: 12) Ecological Information Aquatic toxicity - fish: Aquatic toxicity - daphnia Aquatic toxicity - algae Biodegradability: Bio-accumulation: Mobility: German wgk: 13) Disposal Considerations Disposal methods: Disposal of packaging: 14) Transport Information UN no. Substance indentity no. ADR/RID class: ADR/RID item no. ADR/RID hazard identity no.: IMDG - shipping name: MDG - class: IMDG - packaging group: IMDG - marine pollutant: IMDG - EMS no. IMDG - WAG tabel no.: IATA - shipping name: IATA - class: IATA - subsidiary risk(s): ADNR - class: UK - description: UK - emergency action class: UK - classification: Tremcard no.: 15) Regulatory Information. EEC hazard classification: Risk phases: Safety phases: National legislation: 16) Other Information