Document LpQoNG6NQ9yK1xmV945BDK7Bd

By B. Doyle, Senior Inspector, Department of Minerals and Energy, Pretoria, South Africa The aim of this paper is to explain the principles of the risk assessment process so that those developing their own approaches are aware of the key ingredients. The following points are to be addressed in this pres entation. Background Health performance statistics Purpose of health risk assessment Risk assessment terms Introduction to risk assessment Scope of risk assessment Ten steps to effective risk assessment Reporting and recording Review Conclusion requirements of Section 11 of the Act. That is, risk assessment shall be transparent and will be recorded in accordance with Section 11 (1) (c). The main pur pose of the risk assessment is to enable mine man agers to comply with the requirements of Section 11 (2). The risk assessment must also `loop back' to become a continuous process as required by Section 11 (4)(a). Health performance statistics The following tables indicate the compensation paid out by our industry 1997 1998 1999 Noise Induced Hearing Loss No of Persons Compensation paid 6 131 5 395 6 106 R70 780 674 R68 113 616 R72 321 385 Background During the 1990s, the Mining Industry Summit, was established. A strong recommendation was made to appoint a Commission of Inquiry to investigate all aspects of safety and health in the mining industry. In May 1994 the State President announced the formula tion of a four man Commission of Inquiry with the Rt Actual Expenditure by one mining group for one annum Health Lung Disease Treatment: R 38 million Compensation: R58 million Total: R 96 million Noise Induced hearing loss R 21 million Total R 115 million Hon Mr Justice RN Leon as Chairman. One of the 4 major issues identified by the Leon Commission, which required immediate investigation was that of occupational health. This issue is now ade Safety Fatals and loss time injuries Treatment: R 23 million Compensation: R 22 million Total: R 45 million quately covered in the MHSAfor both disciplines comprising occupational health viz. occupational hygiene and occupational medicine. The purpose of this paper is to pro Mineral Number of Mines No of Occupationally exposed persons No of persons Exposed to AQI>1 % Persons Exposed to AQI>1 Total Compensation Paid Jan-Sept 1998 vide advice on how suitable and suf ficient assessments of risk can be carried out as required by Section Gold Platinum 50 14 25296 61625 12450 672 4.92 1.09 49 118 250 757 678 11(1) of the Mine Health and Safety Act 1996. The way a risk assessment is car ried out depends very much on its Coal Asbestos Others 59 4 161 33971 271 48116 8527 0 2717 25.10 0.00 5.65 1 563 620 9 915 686 3 840 946 final use. In this case, the risk assess ment has to be carried out with the purpose of satisfying the other Total 288 396909 24366 6.14 65 196 180 Worker exposure as per gravimetric results and compensation paid in 1999 Journal of the Mine Ventilation Society of South Africa, January/March 2003 11 2. Purpose of HRA A HRA is a systematic procedure to identify potential health hazards, evaluate the risks arising from those hazards, whilst taking into account the efficiency of existing control measures. Finally, it is also intended to prioritise potential health risks in order to facilitate the drafting of an action plan and occupational hygiene and medical surveillance monitoring programmes. In an attempt to understand the nature of a HRA, it is important to be able to distinguish between the term "hazard" and "risk" as used in occupational health and safety 3. Health risk assessment terms A "Hazard" is conditions, circumstances or objects with the potential to cause harm e.g. hazardous sub stances, noise, thermal conditions, ergonomic factors. "Risk" is the likelihood that harm from a particular hazard will occur: i.e. "The chance of harm or loss" The extent of risk depends on the severity of the harm, and also the number of people affected. 4. Introduction Many people already carry out risk assessments on a day-to-day basis during the course of their work. Already they note changes in working practices, they recognise unsafe working conditions and practices as they devel op and they take the necessary corrective action. The Act requires that this process should become more sys tematic and should be recorded so that the results and the analysis is complete. In particular, employers will have to undertake a systematic general examination of the work activities and then record the significant findings of the risk assessments conducted. The risk assessment process at a mine should be continuous and should not be regarded as a one-off exercise. While it will be necessary to establish a base line, the requirements of the Act will not be satisfied by the creation of a single risk assessment report, which stands for all time. Checklists will need to be developed following risk assessment exercises. In general, a risk assessment involves identifying the hazards present in a work activity or the construction of machinery etc. This is followed by an evaluation of the extent of the risk involved taking into account those pre cautions already being taken. And finally developing systems to control exposures. 5. What is suitable and sufficient Suitable and sufficient risk assessment: a. means considering those risks which are likely to arise because of work and work activities b. should enable development and implementation of action, where appropriate, of systems to manage the risk; c. should be appropriate to the nature of the work so that it remains valid for a reasonable period of time. This will enable the risk assessment process and the significant findings to be used positively, e.g., to change working procedures or to introduce medium to long term controls. 6. Health risk assessments principles There are no fixed rules about how the risk assess ment process should take place. However, there are some general principles that should be followed to ensure that it is suitable and sufficient. The process needs to be very practical and involve management and all employees, whether or not advisors of consult ants assist with the process The following general principles should be followed when conducting a risk assessment: 1. All relevant risks and/or hazards should be sys tematically addressed; Be methodical and thorough; remember that risk assessment is a process. The aim is to identify the significant risks in the workplace and not obscure those risks with excess of information or by concentrating on minor risks. Consider aspects of the work such as the sub stances or equipment used, and the work process or organisation which have the potential to cause harm. Take into account, what controls and other meas ures already exist. The effectiveness of these controls needs to be carefully reviewed. Make sure all processes are in operation There are three essential forms of risk assessment. All are one part of a management system and need to be carried out in mines under the new legislation. These are (not in order of priority): Baseline Risk Assessments Issue Based Risk Assessments Continuous Risk Assessments 1 .Baseline Risk Assessments In compliance with the Act, mines will have to assess where they are in terms of risk, identifying the major risks and thereby establishing their priorities and a pro gramme for future risk control. This baseline risk assessment will need to be comprehensive and may well lead to further, separate more in depth risk assess ment studies. The methodology to be used to determine how many samples need to be taken must be based on internationally acceptable strategies such as NIOSH OSSEM that have tables reflecting how many samples need to be taken to have 90 or 95 % confidence level. The baseline risk assessment should be periodically reviewed, say every one to two years, to ensure that it is still relevant and accurate. Any other studies will need to be incorporated to achieve the `complete picture'. 12 Journal of the Mine Ventilation Society of South Africa, January/March 2. Issue based risk assessments As circumstances and needs arise, separate risk assessment studies will need to be conducted. These will normally be associated with a system for the man agement of change. An additional risk assessment will need to be carried out when, for example: a new machine is introduced into a mine; a system of work is changed or operations are altered; after an accident or a `near-miss' has occurred; new knowledge comes to light and information is received which may influence the level of risk to employees at the mine. An example of this is when the scientific knowledge about the toxicity of a sub stance changes, making previous risk assessment with regard to that substance, invalid. 3. Continuous risk assessments This is the most important form of risk assessment which should take place continually, as an integral part of day-to-day management. It may not use the more sophisticated hazard identification and risk assessment tools which are set out in baseline and issue based risk assessments, but in terms of ensuring safety and elim inating health risks in the workplace, this form of risk assessment is most powerful and important, It will mainly be conducted by frontline supervisors and it is essential that formal training be provided to enable this process to be efficient. Examples of continuous risk assessment include: audits; general hazard awareness linked to a suggestion scheme; and prework assessments using checklists. The emphasis is on "hazard awareness through haz ard identification". 7. Scope of risk assessment The first task when establishing a risk assessment process will be to define the scope of the separate risk assessment exercises. The intention should be that, through the risk assessment process, all of the mine and its activities are comprehensively reviewed and assessed. Some care is therefore needed in laying down the scope of the separate risk assessment exer cises to ensure that no areas or activities are missed. In general, risk assessments are scoped in different ways: 1. Geographically based, such as looking at shafts, haulage's, workshops, etc.; 2. Functionally based, such as drilling, blasting, milling, etc.; 3. Hazard or issue based, such as the hazardous sub stances, noise etc,; It is normally found that the first two of the abovementioned scopes are most effective in ensuring a comprehensive and complete risk assessment, of an operation or activity 8. Team selection Before any risk assessment can proceed, a team has to be selected, background information has to be gath ered and processed and the team has to be prepared for the task ahead. It is vitally important that all these, and the subsequent hazard identification and risk assessments are carried out within a participative framework by involving all stakeholders and their rep resentatives. It is normal to select a team from the workplace being reviewed by taking a vertical slice through the management structure to the lowest levels in the organ isation. Practically, this will mean the front line supervi sor and the team from the workplace being assessed. Specialist expertise should also be brought in exam ple, with regard to psycological factors or ergonomics. The creation of a team for risk assessment is essen tial to ensure their "ownership" of the work and to help bring about a culture change. 9. Ten steps to effective health risk assess ment Risk assessment process The following ten steps provide a systematic proce dure to identify, evaluate and analyse potential health risks in the workplace. Step 1 Subdivide the mine into sampling areas. Example Surface Underground Section 1 Underground Section 2 Underground Section 3 and 4 Subdivide the sampling areas into activities Example Shafts Workshops Stoping Development Raise boring Roving Step 2 The gathering and analysis of information from on- mine sources and from external sources about the activities and workplace is an essential task before the risk assessment can start. Plans of workplace, process-flow diagrams Journal of the Mine Ventilation Society of South Africa, January/March 2003 13  Inventory of job categories, shifts, tasks Material data sheets Hygiene environmental reports Relevant legislation and standards etc previous monitoring reports. Example: Drill Operator Potential risks identified Step 3 This is the most important stage in the risk assess ment process, the identification of hazards, in other words, the adoption of some systematic way of allow ing us to `see' the hazards present in the workplace. If the hazard identification is not carried out carefully, the subsequent analysis of risk and the development of risk control measures become pointless. The identification of hazards is not only an essential part of the risk assessment process, but also acts very effectively to change the way people think, causing them to act more safely and to become more proactive in hazard aware ness. Firstly Identify hazards that may pose a potential health risk to the worker during each task. Simultaneously, also assess any other workplace haz ards that may be relevant. To facilitate this step, an inventory/checklist of each hazard type can be used as a means to be thorough. An example of hazard inventories is reflected in the fol lowing table. NOTE: Remember that this step already makes a distinction between hazard and risk- therefore discard trivial hazards by answering the first question in the inventory. If in doubt, a measurement or sample may be taken as confirmation. Also, make use of findings in Hazardous Substances /airborne pollutants Silica dust Noise Continuous Thermal conditions /Radiation Heat stress noise Ergonomic Factors Vibration from drilling Poor illumi nation, glare Step 4 Note the frequency of exposure Example: Drill Operator Frequency of exposure Health Hazard Silica dust Continuos noise Heat stress Vibration Poor illumination Frequency of exposure Full shift exposure Full shift exposure Full shift exposure Spend 3 hours per shift Entire shift NOTE: The frequency of exposure obtained during the assessment is important And will be applied in the risk score calculation (step 8) Step 5 Establish the health effect and route of entry associ ated with potential exposure. Inventory of hazard types Hazardous substances/ Noise airborne pollutants Thermal conditions/ Radiation Ergonomic Factors Exposure Levels Is potential Exposure possible? Noise Exposure Levels May excessive noise levels be present Temperature/ Radiation Extremes Are excessive exposures likely? Ergonomic Deficiencies Are deficiencies present? What Substance Product produced Raw materials used Materials added By-products liberated Cleaning materials Biological contaminants What Form Dust or fume Mist Gases Vapours Type of Noise Constant Continuous Internment Fluctuating Periodic Non-periodic Impulse Repeated Single ' Sources and cycles Noise sources Cycles per shift Type of condition Type of condition Health/Cold stress Ergonomics Temperatures Seating Radiant heat ' Accessibility ' Humidity Material/handling Wind speed Displays Radiation Illumination Ionising Levels sufficient Non-ionising Glare Stroboscopic effect Contrast Sources and cycles Sources in each instance Ambient conditions Continuous or periodic Thermal comfort cycle Noise and annoyance masking effect 14 Journal of the Mine Ventilation Society of South Africa, January/March NOTE: Information obtained during this step will be applied in the Risk score calculation, i.e. consequence index (step 8) Example Drill Operator Associated health effects/route of entry Health Hazard Health Effects Silica dust Silicosis of the lung (chronic effects) Noise Noise induced hearing loss Heat Stress Heat disorders Vibration White finqer Poor Illumination Reduced visual acuity, eye strain & fatigue, accident risk Route of Entry inhalation N/A N/A N/A N/A Step 6 Evaluate the workplace and work practices for any conditions that may have an impact on the extent of exposure, taking into account existing control meas ures, their efficiency safe work procedures, house keeping, etc. With this information the assessor must be able to predict the probability that exposure will result in a health effect, or incident will follow through to completion. NOTE: Information obtained during this step is essential to allocate an appropriate "probability index" in step 8 Example Drill Operator Workplace and work practices Health Hazard Existing and /or lack of control measures and general comments Silica dust Ventilation systems insufficient to remove dust liberated (vent column leaking) Noise Operator wearing hearing protectors with sufficient attenuation factor No silencers on fan Heat Stress Engineering controls insufficient e.g. cooling Drinking water not available in vicinity Work load high Poor illumination Illumination not uniform - dark areas Lamp reflectors dirty thermal stress: - heat >25,0C wet bulb and/or >32,0C dry bulb and/or >32,0C radiant heat; - cold <10C equivalent chill temperature; and noise: - > 82dBLAeq8h. The tables below indicate the classification bands and the frequency of monitoring to be used when a sys tem of occupational hygiene measurements is to be implemented. Classification Band Table Pollutants (Excluding Toxic Gases &Vapours) CLASSIFICATION BANDS CATEGORY A B C PERSONAL EXPOSURE LEVEL Exposures> the OEL or mixtures of exposures >1 Exposures > 50% of the OEL and < OEL or mixtures of exposures3 0,5 and <1 Exposures > 10% of the OEL and < 50% of the OEL or mixtures of exposures > 0,1 and < 0,5 Toxic Gases & Vapours CLASSIFICATION BANDS CATEGORY A B PERSONAL EXPOSURE LEVEL Exposures > the OEL or mixtures of exposures >1 Exposures > 50% of the OEL and the OEL or mixtures of exposures > 0,5 Step 8 Where there is no stipulated hazard levels set out for certain health hazards then the risk index as is depict ed below must be used. Determine the extent of exposure. Calculate the risk score For this purpose, standard indices for each factor may be used as reflected in the tables below. The fol lowing equation can be used: Step 7 The OHSC has identified when occupational hygiene measurement systems need to be established. The regulation is as follows: System of occupational hygiene measurements The employer must establish and maintain a system of occupational hygiene measurements, as contem plated in section 12, of all working places where the fol lowing hazard limits prevail: airborne pollutants: - particulates > of the occupational exposure limit; - gases and vapours > of the occupational exposure limit; Risk = Consequence (C) x Frequency (F) Frequency (F) = Exposure (E) x Probability (P) Consequence = "the degree of harm" The potential severity of the injuries or ill health and/or the number of people affected Frequency = frequency of occurrence Exposure = How often and for how long the workers are exposed to the hazard Journal of the Mine Ventilation Society of South Africa, January/March 2003 15 Probability = The chance that a person, or persons, will be harmed during the exposure period Frequency Scale Frequency index 5 4 3 2 1 Description Hazard permanently present Hazard present once or periodically per shift, less than 6 hours Hazard present once or periodically per shift, less than 4 hours Hazard arises once a week Hazard arises once a year or very rarely Consequence Scale Consequence index Description 5 Death 4 Permanent incapacity 3 Considerable discomfort with subsequent recurrina incapacity 2 Reversible health conditions with short term health effects 1 No human injury expected during normal exposure Probability Scale Probability index 5 4 3 2 1 Description Inevitable (100% chance) Very likely (80 % chance) More than even chance (60%chance) Less than even chance (1-50%chance) Practically impossible(< 1 %chance) Example: Drill Operator Calculate risk rating Health Hazard Vibration Illumination Frequency Consequence Probability Risk score 54 2 40 (medium) 52 2 20 (low) Compile a prioritised list of risks by using the above table, which will show the highest numbers and most important priorities to be considered first. Example: Prioritise risks Drill Operator Prioritise Risks Health Hazard Vibration Illumination Risk Rating Medium Low One can also calculate a composite score for each work area and department to establish which depart ments have the highest significant heath risk. NOTE: Remember that this method is only a key to facilitate the process and to allocate an appropriate risk rating. For example, the decision making process of the assessment team still depends on their discretion, and risks with borderline cases (e.g. low to medium) may be changed in order to be included in the monitoring programme. Step 10 Compile occupational hygiene monitoring and med ical surveillance programmes based on steps 7, 8 and 9, as well as an overall action plan that incorporates all actions to be taken. Proposed monitoring programmes and action plans will be determined by findings obtained during the assessment and by relevant legislation and standards applicable for each significant health risk. Remember: This step requires a decision process of a subjective nature - especially the probability index. Try to think objectively and judge the scenario holistically. Remember - the probability index will be higher with a risk where PPE is used compared to a risk controlled by sufficient engineering control measures. Step 9 Quantify and list the priority of action. All the signifi cant risks in the table shown in Step 8 can be prioritised according to risk scores calculated. The urgency or priority of action required in respect of a particular risk can be quantified as shown in the table below. Risk score Actions 60-125 (High) Immediate action required. Monitoring should be conducted immediately to 30 - 59 (medium) < 30 (low) introduce interim control measures Risk requires urgent attention as soon as possible Monitoring of risks required. No immediate action necessary. Risk currently under control, but requires regular revision. Monitoring not a requirement Example 1 Drill Operator Proposed occupational hygiene monitoring pro gramme. Activity Area Stoping Occupational Category Driller Proposed Monitoring Gravimetric sampling (c- quartz) Noise Survey for hearing conservation Vibration Survey Illumination Survey Example 2 Dill Operator Proposed medical surveillance programme 16 Journal of the Mine Ventilation Society of South Africa, January/March Activity Area Stoping Occupational Proposed Surveillance Category Driller 1. Baseline Medical surveillance to include Medical and occupational history Physical examination Lung function test Audiometric examination Vision test Urinalysis 2. Continuing medical surveillance, e.g. Annual audiomerty Chest X-rays 2 yearly 2 yearly lung function test Physical examination with emphasis on muscle-skeleton system, spine and back 10. Reporting and recording It is vitally important that the risk assessment is recorded so that there is a reliable statement and evi dence of what appropriate actions management is tak ing to protect health and safety. The risk assessment need to be an integral part of an employer's overall approach to health and safety, and its results need to be linked to other health and safety records and docu ments, such as the statement of health and safety poli cy. Ultimately, it should become an integral part of a company's overall management system. Whatever the format of the risk assessment report, it should be easily accessible to employees, their repre sentatives and inspectors. The record of the risk assessment may consist of several documents, which describe procedures and safeguards, the approach used and the results of the exercise. Although record ing of the risk assessment process is important, the generation of a system on paper alone is not sufficient to ensure compliance with section 11 of the mine health and safety act. Producing documentation should not detract from the major purpose of risk assessment; that is, to improve the management of risks and thereby to ensure the health and safety of employees. It is vitally important that the recorder of the risk assessment reports those findings, which are judged to be significant. These include: 11. Review Section 11 (3) (a) of the Act requires managers to review and, if necessary, modify their risk assessments since they should not be a one-off activity. Risk assess ment is a continuous process and as work changes, the hazards and risks may change and therefore the risk assessment process must also change. If changes occur the risk may change. Need to use risk assessment; to manage change. Part of good management/business practise If knowledge changes, the risk may change. Particularly after an accident, ill health accident need to revisit risk assessment. 12. Conclusion The first and foremost purpose of a HRA is to identi fy potential health hazards and protect the health of all employees in every work area. Unfortunately, the per son responsible for HRAs is mostly guided by only vague requirements set out in the legislation and regu lations. If the guidelines in this presentation are followed and the assessment procedure is conducted thor oughly and methodically, most obstacles associated with the risk assessment process will be overcome and all significant risk will be targeted from the start. The Mine Ventilation Society of S.A. 6(jth Anniversary 1944 -2004 The Society would like to get in touch with any Society Members who were present at the Society's Inaugural Meeting held in 1944 1. The major hazards identified in the assessment. That is, those hazards which, if the are not properly con trolled pose serious risks to employees or others who may be affected. 2. A review of the existing safety measures and the extent to which they are effective in controlling the risks. 3. Those who may be affected by the significant risks or major hazards including those groups and employ ees who are especially at risk KINDLY CONTACT THE SECRETARY SUE MOSELEY AT (Oil) 487-1073 Email: minevent@global.co.za Journal of the Mine Ventilation Society of South Africa, January/March 2003 17