Document RpX6ejMvLdLRn39y7ypk3jeBB

Guidance Note EH 32 from the Health and Safety Executive ItCAf****% Control of exposure to talc dust 4* R&S 116781 ( ' i Environmental Hygiene Series 32 (July 1982) These Guidance Notes are published under five subject headings: Medical, Environmental Hygiene, Chemical Safety, Plant and Machinery and General. INTRODUCTION 1 This Guidance Note draws attention to the possible health risks which could result from industrial exposure to talc dust and advises on precautions which should be taken to protect workers. As with all dusts in the work ing environment, the concentration of talc dust in air should be kept as low as is reasonably practicable. Para 7 gives guidance on exposure limits. (a) in cosmetic products; (b) as surface dusting material or 'anti-tack' agent in the rubber, roofing felt manufacture, plastics and electric cable making industries, and in specialised foundry sands; (c) in paint, paper, plastics, ceramic and refractory products; (d) a free flowing agent or 'anti-caking' medium in the fertiliser and insecticide compounding industries. EFFECTS OF EXPOSURE DESCRIPTION 2 Talc is a mineral which in its pure form is hydrated magnesium silicate. It often naturally occurs with other minerals. These may include magnesite, dolomite, chlorite and quartz. Specialist grades of talc sometimes contain tremolite, anthophyllite*, actinolite and serpen tine,* some of which may occur in fibrous form. 3 Generally industrial talc has the appearance of a white or greyish white powder with a crystalline platy structure, the size of the platelets being determined mainly by the degree of milling carried out on the raw material. Finely ground talc is sometimes termed 'French chalk'; soap stone (or steatite) is a coarser form which usually feels greasy to the touch. SOURCE 6 Studies amongst workers in the mining and milling industries 1,2,3 have shown that excessive inhalation of talc dust (whether pure, or mixed with other mineral dust) over a period of years can cause respiratory disease. The disease may be non-specific characterised by a persistent cough, sputum and breathlessness, as a result of airway irritation and obstruction. Where substantial quantities of dust enter the lungs, long-term effects including talc pneumoconiosis may occur. In the past the different appearances in the radiograph and clinical presentations reported in medical literature have probably resulted from the range of materials to which people have been exposed varying from substantially pure platy talc to mixtures with a high percentage of fibrous mineral. Although there is insufficient data from the user indus tries to confirm these health effects it would be prudent to adopt the recommendations of this Guidance Note to restrict exposure. 4 In 1980 talc consumption in Great Britain was of the order of 60 000 tons. The main sources of supply are Norway, the Shetlands, France, China, Italy, Australia, Spain, India and the USA. Samples of talc examined in Great Britain by HSE have generally been found to be fibre-free but occasionally to contain insignificant quantities of fibre. Free silica content varies from low (less than 1%) up to approximately 5% quartz. INDUSTRIAL USES 5 The use of talc for industrial purposes in Great Britain falls mainly into the following categories: EXPOSURE LIMITS 7 Guidance on exposure limits is published annually by the Health and Safety Executive4. Exposure to talc should not exceed 10 mg/m3 for total talc dust in air and 1 mg/m3 for respirable talc dust in air, 8 hour time weighted average (TWA) concentrations and should be further reduced where reasonably practicable*. Inspectors will use these limits when assessing compliance with the Health and Safety at Work etc. Act 1974 and relevant statutory provisions. 'See para IS, when these minerals are present in their fibrous form. TBut see para 16 and Guidance Note EH101 should mineralogical examination to talc indicate the presence of asbestos. 1 ASSESSMENT OF WORK HEALTH SURVEILLANCE R&S 116782 8 Work involving talc should be assessed to detect sources of dust, to determine the levels of exposure and to identify any necessary improvements to existing controls or the provision of new controls. The work should be re-assessed whenever changes are introduced which may significantly affect exposure. 9 Section 6 of the Health and Safety at Work etc. Act 1974 (HSW Act) requires manufacturers, suppliers etc. to make available adequate information about the results of any relevant tests and about any conditions necessary to ensure that a substance will be safe and without risk to health when properly used. This information could be useful in the selection of the grades of talc to be used and when assessing the nature of exposure resulting from the work. 14 General advice on health surveillance is contained in Guidance Note MS 189. Where there is substantial exposure to talc some reports have demonstrated that there can be long-term health effects. It would therefore be prudent in such cases to extend health surveillance to include the preservation of records of health examinations and environ mental sampling for an appropriate period. STATUTORY REQUIREMENTS 15 No specific regulations have been made under the Factories Act 1961 or the HSW Act to deal with exposure to talc dust, but control is required under Section 2 of the HSW Act and Sections 1,4 and 63 of the Factories Act. CONTROL OF EXPOSURE 10 When exposure to talc dust cannot be avoided the introduction of material, plant and process controls will need to be considered. Local exhaust ventilation6 may be necessary depending on the degree of exposure. Exposure can also be reduced by careful handling and by applying good standards of housekeeping. Spillages should be removed by a dustless cleaning method e.g. vacuum cleaning. 11 In some cases protection in the form of suitable respiratory protective equipment (RPE) may also be necessary. British Standard BS 427S: 19747 makes reco mmendations on the selection, use and maintenance of RPE. Respirators which have been approved under statutory provisions by the Health and Safety Executive are listed in leaflet No F 2486s. 16 The Asbestos Regulations 1969 may apply where mineralogical examination of talc indicates the presence of asbestos fibres and the mineral is being used at a work place subject to the Factories Act 1961. 17 The Alkali etc. Works Regulation Act 1906 and Alkali etc. Works Orders 1966 and 1971 relate to emissions from works in which minerals are subjected to any size reduction, grading or heating by processes giving rise to dust. Many talc manufacturing and processing operations come within this definition and must therefore satisfy the 'best practicable means' requirements of the Health and Safety Executive Alkali and Clean Air Inspectorate. APPENDIX: SAMPLING AND MEASUREMENT SAMPLING AND MEASUREMENT 12 Where the information available on the levels of exposure to dust containing talc is not sufficient for the work to be properly assessed or where exposure may be in excess of the limits referred to in para 7, the airborne concentration to which persons are exposed should be measured in order to: (a) verify whether the 8-hour time-weighted average concentration of dust containing talc in the breathing zone exceeds these limits on a given occasion; and (b) monitor the effectiveness of material, plant and process controls. 13 The sampling strategy should be determined having regard to the nature of the work and the duration of exposure. The results obtained should be representative of personal exposure averaged over an 8-hour period. The measuring methods used by HSE for sampling total and respirable dust are described in the Appendix. 1 The techniques in current use by the Health and Safety Executive for measuring time weighted average concentrat ions of 'respirable' and 'total' dust containing talc in the breathing zones of persons at work are described below. In both cases, use is made of personal sampling equipment consisting of a filter holder, worn high on the person's chest (e.g. attached to lapel) within 300mm of his nosemouth region. The filter holder is connected to a battery operated, portable pump which is attached to a belt worn around the waist and which is capable of running continuously for 8 hours. Respirable dust sampling 2 The equipment used for respirable dust sampling consists of a cyclone type filter holder fitted with a pre weighed glass fibre filter (either 25 mm or 37 mm diameter) and connected via a flow smoother to either a vane type pump or a diaphragm type pump. The design of the cyclone type holder and the sampling flow rate are such that only the respirable fraction of the dust, as defined by the Medical Research Council10'11, reaches the filter. 2 r ( Total dust sampling 3 The equipment used for total dust sampling consists of a multi-orifice filter holder, as illustrated below, fitted with a pre-weighed, 25mm diameter, glass fibre filter. The filter holder is connected via a flow smoother to a vane type or diaphragm type pump. The pump flow rate is maintained at 2'Q litre/min. The filter holder is attached to the wearer in such a way that the orientation of the filter is close to the vertical plane. Air sample volume 4 For each sample obtained by the use of an unstabilised pump, the flow rate is checked, and adjusted if necessary, against an external flowmeter at the beginning and end of the sampling period and at one-hourly intervals during sampling. The sample volume for each interval is calcu lated by multiplying the average of the flow rates at the beginning and end of the interval by the interval duration (in minutes). The total sample volume, V, (m3) is then given by the sum of the volumes for these intervals. Where a stabilised-flow pump is used, the sample volume, V, is given by the flowrate (checked against an external flowmeter) multiplied by the sampling period. REFERENCES 1 Gamble, J etaI (1980) 'Cross Sectional Epidemiologic and Industrial Hygiene Survey of Talc Workers Mining Ore from Montana, Texas and North Carolina' in: proceedings of the National Workshop on substitutes for Asbestos, Arlington Va, July 14-16, 1980. U.S Environmental Pro tection Agency EPA 560/3-80-001 November 1980. 2 Leophonte Petal (1976) 'Les Pneumoconioses Par Le Talc', Archives Das Maladies Professionalies, 37(6): 513-532. 3 Selevan SGetai (1979) 'Mortality Patterns among Miners and Millers of Non-Asbejtiform Talc: Preliminary Report'. Journal of Environmental Pathology and Toxicology, 2: 273-284. 4 Guidance Note EH 15 Threshold Limit Values. 5 Guidance Note EH 10 Asbestos -- hygiene standards and measurements of airborne dust concentrations. 6 'Principles of Local Exhaust Ventilation', Joint Standing Committee on Health, Safety and Welfare in Foundries, First Report of the Sub-Committee on Dust and Fume. HMSO. 'O' ring seal Filter support grid Filter (glass fibre) 25mm dia End cap with seven quispaced inlet holes, 4mm dia. 7 BS 4275: 1974, Recommendations for the Selection, Use and Maintenance of Respiratory Protective Equip ment. BSI. 8 F 2486, Certificate of Approval (Respiratory Protective Equipment). HMSO. 9 Guidance Note MS 18, Health surveillance by routine procedures. 10 Hamilton R J & Walton W H (1961) in `Inhaled Particles and Vapours' (Ed. C N Davies) pp 465-475 (Pergamon, Oxford). Exhaust port for connection to pump 11 Orenstein A S (Editor) (1960) 'Recommendations adopted by the Pneumoconiosis Conference', Proceedings of the Pneumoconiosis Conference', Johannesburg, 1959 pp 619-621 (Churchill, London). Filter weighing and calculation of TWA concentrations 5 Filters are re-weighed after use, on an electro-balance capable of reading 10 pg to obtain the weight, W, (mg) of dust collected (after treatment to allow for humidity effects). The average concentration of dust for the sampling period, in mg/m3, is then given by dividing weight, W, by volume V. FURTHER INFORMATION This Guidance Note is produced by the Health and Safety Executive. Further advice on this or any other publications produced by the Executive is obtainable from Baynards House, 1 Chepstow Place, London W2 4TF, or from Area Offices of the HSE. R&S 116783 3 GUIDANCE NOTES General Sarin Medical Series GS 1 GS 2 GS 3 GS 4 GS 5 GS 6 GS 7 GS 8 GS 9 GS10 GS It GS 12 GS 13 GS 14 Fumigation using methyl bromide Metrication of construction safety regulations Eire risk in the storage and industrial use of cellular plastics Safety in pressure testing Entry into confined spaces Avoidance of danger from overhead electrical lines Accidents to children on construction sites Articles for substances for use at work - guidance for designers, manufacturers, importers, suppliers, erectors and installers Road transport in factories Roofwork: prevention of falls Whisky cask racking Effluent storage on farms Reporting of accidents to pupils and students Provision of sanitary conveniences and washing facilities in agriculture MS 3 MS 4 MS 5 MS 6 MS 7 MS 8 MS 9 MS 10 MS 12 MS 13 MS 15 MS 16 MS 17 MS 18 MS 20 Skin tests in dermatitis and occupational chest disease Organic dust surveys Lung function Chest x-rays in dust diseases Colour vision Isocyanates - medical surveillance Byssinosis Beat conditions and tenosynovitis Mercury - medical surveillance Asbestos Welding Training of offshore sick-bay attendants (Tig-medics') Biological monitoring of workers exposed to organophosphorus pesticides Health surveillance by routine procedures Pre-employment health screening Environmental Hygiene Series Chemical Safety Series EH 2 Chromium health and safety precautions CS 1 Industrial use of flammable gas detectors EH 4 Aniline - health and safety precautions CS 2 The storage of highly flammable liquids EH 5 Trichloroethylene: health and safety precautions CS 3 Storage and use of sodium chlorate EH 6 Chromic acid concentrations in air CS 4 The keeping of LPG in cylinders and similar containers EH 7 Petroleum based adhesives in building operations CS 5 The storage of LPG at fixed installations EH 8 Arsenic - health and safety precautions CS 6 The storage and use of LPG on construction sites EH 9 Spraying of highly flammable liquids Plant and Machinery Series EH 10 Asbestos - hygiene standards and measurements of airborne dust concentrations PM 1 PM 2 PM 3 PM 4 PM 5 PM 6 PM 7 PM 8 PM 9 PM 10 PM 13 PM 14 PM IS PM 16 PM 17 PM 18 PM 19 PM 20 PM 21 PM 22 PM 23 Guarding of portable pipe-threading machines Guards for planing machines Erection and dismantling of tower cranes Safety at high temperature dyeing machines Automatically controlled steam andhot water boilers Dough dividers Lifts Passenger carrying paternosters Access to tower cranes Tripping devices for radial and heavy vertical drilling machines Zinc embrittlement of austenitic stainless steel Safety in the use of cartridge operated tools Safety in the use of timber pallets Eyebolts Pneumatic nailing and stapling tools Locomotive boilers Use of lasers for display purposes Cable-laid slings and grommets Safety in the use of woodworking machines Mounting of abrasive wheels Photo-electric safety systems EH 11 Arsine health and safety precautions EH 12 Stibine health and safety precautions EH 13 Beryllium health and safety precautions EH 14 Level of training for technicians making noise surveys EH 15/80 Threshold limit values EH 16 Isocyanates: toxic hazards and precautions EH 17 Mercury - health and safety precautions EH 18 Toxic substances: a precautionary policy EH 19 Antimony - health and safety precautions EH 20 Phosphine health and safety precautions EH 21 Carbon dust health and safety precautions EH 22 Ventilation of buildings: fresh air requirements EH 23 Anthrax: health hazards EH 24 Dust accidents in malthouses EH 25 Cotton dust sampling EH 26 Occupational skin diseases: health and safety precautions EH 27 Acrylonitrile: personal protective equipment EH 28 Control of lead: air sampling techniques and strategies EH 29 Control of lead: outside workers EH 30 Control of lead: pottery and related industries EH 31 Control of exposure to polyvinyl chloride dust EH 32 Control of exposure to talc dust PM 24 Safety at rack and pinion hoists PM 25 Vehicle finishing units: fire and explosion hazards PM 26 Safety at lift landings PM 27 Construction hoists PM 28 Working platforms on fork lift trucks PM 29 Electrical hazards from steam/water pressure cleaners etc. R&S 116784 HMSO 50p net ISBN 0 11 883544 0 Crown copyright 1982 First published 1982 Printed in England for Her Majesty's Stationr Robendene Ltd., Amersham. 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