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Archive for Occupational Hygiene

Workplace Noise Exposure and the Queensland Noise Legislation

Workplace noise-induced hearing loss is still a major compensable disease in Queensland workplaces. Noise-induced hearing loss is caused by excessive noise in the workplace. A worker may have an entitlement to compensation for hearing loss if their employment was a significant contributing factor causing the loss of hearing.

The Queensland Work Health and Safety Act 2011 places responsibility for managing workers health and safety risk on the ‘persons conducting a business or undertaking’ (PCBU). The WHS Regulations 2011 detail responsibilities for the PCBU to ensure noise exposure does not exceed the exposure standard and to provide hearing tests for certain workers.

In Queensland noise is prescribed in Part 4.1 of the Work Health and Safety Regulation 2011.  For this standard excessive noise is a level of noise above an 8-hour equivalent continuous A-weighted sound pressure level (LAeq,8h) of 85dB(A) and a C-weighted peak sound pressure level exceeding 140 dB(C). The LAeq,8h represents a steady noise which, if averaged over 8 hours, equates to a daily noise exposure.

It is important to understand that this standard should not be considered a safe exposure level, where over a period of time there would be no damage to someone’s hearing or potential for other health effects. Rather, the standard of 85 dB (A) is considered to be an ‘acceptable’ risk for the working population.

For instance, research indicates that after an exposure to 85 dB (A) over a 40 year working life, 74% of exposed males can expect to experience a 6% hearing disability while 47% of females can expect to experience a 6% hearing disability.

The implication for the workers is that, even with the current noise exposure standard, a large percentage of the workforce can expect to have incurred significant hearing loss by the time they cease working. Therefore, it is imperative that noise exposure is kept below the exposure standard.

The Managing Noise and Preventing Hearing Loss at Work Code of Practice 2011 prescribe ways of preventing or minimising risks to workers from exposure to excessive noise at a workplace.

Effective noise management requires assessment of noise levels and workers exposure, engineering noise control, personal protective equipment, audiometric testing (hearing tests) and worker training.

A noise assessment may be required to quantify the noise exposure risk to workers. Workplace Noise Assessments should be conducted by a competent person (occupational hygienist) to meet the requirements of AS1269.1: 2005 Measurements and Assessment of Noise Immission and Exposure. .

In most situations the noise assessment involves a combination of personal exposure measurements and noise level measurements for plant and equipment. Where required noise contour maps can be developed.

The period between noise assessments should be determined by management in consultation with workers through consultative processes. The noise assessment should be repeated at intervals not exceeding five years or whenever there is a significant change to the conditions that affect exposure.

For information on workplace noise monitoring click here.

For information on plant noise assessments click here.

For further information on how we can assist you with noise assessment services call our office or use our contacts page to forward a request for further information.

Sunshine Coast, Brisbane, Gold Coast and Regional Queensland

A Strategy for Assessing and Managing Occupational Exposures

Introduction to Assessing and Managing Occupational Exposures

In Australia we have a legal requirement to protect all who work on or visit our sites or premises from occupational illness or injury. To maintain competiveness in a global economy it is essential that this is achieved through an effective and efficient program. Prior to developing workplace monitoring or health surveillance programs a comprehensive understanding of workplace exposures is required to ensure appropriate cost-effective programs are developed.

Many people carry out risk assessment on a day-to-day basis during the course of their work. They note changes in working practices, they recognise unsafe working conditions and practices, and often they take appropriate corrective action. However risk assessments need to be conducted systematically to deliver real and lasting benefits to worker health.

The American Industrial Hygiene Association (AIHA) Strategies for Assessing and Managing Occupational Exposures prescribes a methodology which when adopted provides a systematic and cost-effective program for assessing workplace exposures. This program has been adopted for use in the Australian work environment through the Australian Institute of Occupational Hygienist (AIOH) Simplified Occupational Hygiene Risk Management Strategies Guidelines.  The guideline has been developed to meet Safework Australia’s requirements and will assist in achieving compliance with the Model Work Health & Safety Laws which will be enacted early 2012.

Occupational Health Hazard Identification

Health hazard identification is the first step to develop an occupational hygiene program. This process will develop a list of the stressors that the workforce is potentially exposed to. These will be under the categories of Chemical (Solvents, Pesticides), Physical (Vibration, Heat, Noise), Biological (Mould) and Ergonomic. The health hazard identification needs to be conducted in consultation with operational staff, the process usually involves:

  • A review of the materials/chemicals and their material safety data sheets (MSDS);
  • A review of the process, including exposure scenarios e.g. the tracking of trace amounts of highly toxic substances;
  • A walk-through survey, and consultation with operational personnel regarding processes, equipment, materials used, physical environment, products / by-products, etc;
  • A review of documented monitoring or information from similar types of assessments;
  • A review of reported incidents.

Establishing Similar Exposure Groups for Occupational Health Hazards

The next step is to establish Similar Exposure Groups. A Similar Exposure Group (SEG) is a group of people having the same general exposure profiles because of the similarity and frequency of the tasks they perform and materials and process with which they work. A properly defined SEG provides the ability to use data from a relatively small sample of the exposure population to predict the likely chronic health exposures of the group as a whole.

Risk Assessment for Health Hazards

Assessments involve qualitative and semi-quantitative risk assessments that are performed to identify potential exposures that require inclusion in the monitoring program. This is a risk management process to establish the priority exposures for further review and uses surrogate data, modelling and the judgment of the hygienist, engineers, managers and operators. Resources for health surveillance and workplace monitoring can then be focused on the priority areas where further information is required to define exposures.

Health Surveillance

Health surveillance, of a person, means monitoring the person to identify changes in the person’s health status because of exposure to a hazardous chemical.

The Workplace Chemicals Model Regulations require that health surveillance be conducted when:

  • there is a significant risk to the health of a worker arising from exposure to a hazardous chemical listed at Schedule 3; or
  • a risk assessment identifies a significant risk to the health of a worker arising from exposure to any hazardous chemical and there are valid techniques for detecting indications of the health effect; or
  • a valid method for determining biological exposure exists for a hazardous chemical and there is uncertainty, based on reasonable grounds, as to whether a safe level may be exceeded.

The Model Work Health and Safety Regulations provide specific requirements for health surveillance for workers conducting specified lead work or certain asbestos removal or maintenance work.

Blanket heath surveillance programs (full health surveillance for all workers) are extremely expensive. They disrupt workforce scheduling and create unnecessary anxiety with the workforce (why am I getting health surveillance for asbestos when I have been told that I do not work with asbestos containing material).

Systematic hazard identification and risk assessment to determine occupational exposure profiles assists with focussing health surveillance on the groups where a need has been identified.

Workplace Monitoring

Monitoring means to survey regularly all measures which are used to control hazardous chemicals in the workplace. This includes the monitoring of atmospheric contaminants, but does not include biological monitoring which is an element of health surveillance.

The Workplace Chemicals Model Regulations require that monitoring is undertaken to determine the concentrations of hazardous chemicals in the workplace when:

  • there is uncertainty, based on reasonable grounds, as to whether an exposure standard may be exceeded or;
  • monitoring is necessary to determine whether there is a risk to health.

Blanket monitoring programs are extremely expensive and can disrupt workforce scheduling.

Systematic hazard identification and risk assessment to determine occupational exposure profiles assists with focussing monitoring programs on the groups where a need has been identified.

Our Experience ?Assessing and Managing Occupational Exposures

Our principal consultant, Maurice Barnes, has professional qualifications in Science, Occupational Health and Safety and Occupational Hygiene and is a Chartered Profession Member of the Safety Institute of Australia and a Member of the Australian Institute of Occupational Hygienist. Maurice has over 15 years experience in the field of occupational health and safety including experience conducting audits and risk assessments for waste and treatment facilities including sewerage treatment plants.

Recent projects completed by our principal consultant include:

Conduct health hazard identification and risk assessment and develop health surveillance and monitoring programs for Australian Navy Ships and Submarines. This project was completed on behalf of the Defence Centre of Occupational Health under direction from the Defence Minister.

Assistance to regional councils in the conduct of risk assessments and development of work method statements for their waste water and treatment facilities including the sewerage treatment plant.

Conduct of detailed risk analysis and personnel exposure monitoring for maintenance personnel exposure to contaminated soil and water during site remediation work.

Some Benefits of implementing a Strategy for Assessing and Managing Occupational Exposures

Cost Savings for Health Surveillance Program

Without systematic hazard identification and risk assessment a blanket health surveillance program is often implemented.  Through implementing a strategy for assessing and managing hazards a targeted health surveillance program can be adopted. The below table shows estimated costs of a blanket health surveillance program compared to a targeted approach for a workforce with 500 operational people.

Type of Assessment Full Assessment Partial Assessment Minimal Assessment Total Cost / Year
Cost of Assessment $600 $400 $200  
Blanket Health Surveillance Program 500 employees - - $300,000
Targeted Health Surveillance Program 100 employees 200 employees 200 employees $110,000

The cost of a health surveillance program is not necessarily a new cost for organisations, in many cases health surveillance is already conducted i.e. medical checks for all workers who conduct confined space entry and hearing assessments. Adopting a systematic strategy is about integrating and targeting resources so that they are effective and compliance is achieved.

Cost Saving of Workplace Monitoring Program

Similar savings can be made in workplace monitoring programs. This is harder to quantify as we don’t yet know what monitoring is required. In a lot of situations using this assessment methodology allows risk assessments to be conducted using surrogate data (exposure data from other workplaces) and modelling, again providing significant savings. In some situations surrogate data and modelling is more reliable and provides stronger evidence of the exposure profile as it draws from large assessment programs that an individual organisation could not resource.


The cost savings in health surveillance and workplace monitoring are advantages of adopting this strategy but they are not the main benefit. A thorough understanding of exposures allows the occupational hygiene program, including control efforts, to be prioritised to protect employees and manage exposure related risks.  It also puts the organisation in position to manage the unpredictable changes that will occur both in knowledge of health-effects of environmental agents and in society’s tolerance of workplace exposures.

Development of a comprehensive exposure assessment program is encouraged because a comprehensive program is the best way for organisations to understand and manage the ever-broadening realm of occupational health related risks.

For detailed advice on assessment and specific control measures for your workplace contact our consultants.

For further information on occupational health and hygiene hazards click here.

Haztek: Servicing Sunshine Coast, Brisbane, Gold Coast and Regional Queensland