An evaluation of occupational health risk assessment methodologies from South African enterprises: noise risk assessment field study

Background: The South African occupational health and safety regulations, prescribing risk assessments be conducted by employers, are non-prescriptive with regard to the tools and techniques to be used. Consequently, companies freely adopt the numerous available tools and techniques from which risk management decisions are derived. Thus, risk management, ensuing from the results derived from these tools and techniques, is likely to vary from company to company. Objective: The objective of the study was to evaluate risk assessment processes and methodologies that are used and recorded in noise risk assessment reports, in four manufacturing companies. Methods: This was a case study, whereby risk assessment records were obtained from four South African companies with different operational units, from the manufacturing and utilities sectors. Results: There were inter- and intra-company variations in the processes related to the legal context in which the risk assessments were conducted, the risk assessment tools and techniques used, the risk criteria definitions, the statements about the effectiveness of controls in use, and the risk evaluation outcomes. Inter- and intra-company variations in risk rankings and risk prioritisation outcomes were also observed ­ a consequence of the risk perceptions of the assessors assigning a risk level to the noise hazard. In some instances, the adopted risk assessment tools and techniques categorised the risk from noise that was at or above regulated health and safety standards as 'insignificant', which those companies used as justification for taking no further measures to eliminate or reduce the risk. Conclusion: The use of different risk assessment processes, tools and techniques resulted in some facilities categorising noise as an insignificant hazard, which may contribute to high noise emissions and uncontrolled exposures.

Noise exposure abatement: a perspective from industry occupational health risk assessment reports

Background: Occupational health risk assessments are building blocks for occupational health programmes, allowing for the rating of identified risks and the continuous re-evaluation of the effectiveness of abatement measures. In South African industry, occupational health risk assessments are formally documented in reports, which can be presented as demonstration of legal compliance with legislation. Objective: To identify noise abatement measures recorded in noise risk assessment reports of four manufacturing companies and to rate their effectiveness. Methods: We analysed the occupational health risk assessment reports from 21 operational facilities in four South African companies from the manufacturing and utilities sectors to evaluate, through document analysis, the recorded noise abatement measures. Noise abatement measure effectiveness was rated using a preassigned effectiveness percentage scale. Results: Administrative controls and hearing protection devices were the most commonly used noise exposure abatement measures, but hearing conservation programmes were generally poorly formulated. There were inter- and intra-company differences in the qualitative risk assessment approaches used for rating or ranking the noise risk, which led to different risk conclusions and prioritisation outcomes. The calculated control effectiveness of the abatement measures showed that noise exposure remained largely unacceptable: 16 of the 21 operational units had unacceptable noise exposures, four had tolerable exposures, and one had broadly acceptable exposures. Conclusion: The four companies' common noise abatement measures, as elements of formalised hearing conservation programmes, which included administrative controls and hearing protection devices, were not effective in reducing noise exposure to the broadly acceptable level, reflective of limited use of engineering controls.