Occupational Hygiene Monitoring: Chemical Stressors

The Occupational Health and Safety Act as well as the Mine Health and Safety Act requires that the Hazardous Chemical Substances (HCS) exposure levels of employees in their working environment be determined and reported on, should the exposure levels exceed the prescribed Occupational Exposure Limits (OEL), mitigating measures must be implemented to reduce exposures to hazardous chemical substances that exceed the prescribed OEL.

Under the guidelines of the Hazardous Chemical Substances Regulations set out in the Occupational Health and Safety Act, the employer is required to determine:

1. The HCS to which an employee may be exposed to,
2. What effects the HCS can have on an employee,
3. Where the HCS may be present and in what physical form it is likely to be,
4. The route of intake by which and the extent to which an employee can be exposed,
5. The nature of work, process and any reasonable deterioration in, or failure of, any control measures.

Once this information is obtained a monitoring programme can be implemented to determine the extent of the exposure to HCS’s in the workplace.

The HCS exposure levels obtained during the monitoring programme should be compared to the OEL as prescribed in the Hazardous Chemical Substances Regulations contained in the Occupational Health and Safety Act.

In some instances, the Occupational Hygiene Monitoring Programme will include not only the monitoring of exposures to the hazardous chemical substances and comparing the results to the OEL’s, but also include the comparison of the results from biological samples to the BEI’s to complement the monitoring programme.

The Department of Employment and Labour published a notice that requires all industries handling, manufacturing and producing Silica dust to submit annual reports to the Department starting from 1 January 2009 indicating the following:

1. The number of samples taken and analysed,
2. The chemical composition of the dust,
3. The concentrations of the constituents,
4. Whether compliance is achieved with the new Occupational Exposure Limit for Silica, if not complying, what steps are implemented to comply with the exposure limit within six months from the date of the notice being gazetted.

The Occupational Hygiene Monitoring Programme requires that the employer conducts exposure monitoring every 12 months.

The above directive supersedes the requirements of the Hazardous Chemical Substances Regulations and requires the employer to now compile an exposure monitoring programme that meets the guidelines and conducts continuous exposure monitoring throughout the twelve (12) month period.

The directive also requires that the employer reports the results of the monitoring programme to their office on an annual basis as per the Silica Exposure Compliance Tool document.

At the Mine Health and Safety Summit of 2003, the tripartite stakeholders in mining agreed to targets and milestones, which are aimed at addressing the major health and safety concerns of the sector.
The milestones are considered to be intermediate steps to achieving targets of zero fatalities and injuries, silicosis elimination and the elimination of noise-induced hearing loss.

The Department issued guidance notes to employers with regard to establishing an Occupational Hygiene Monitoring Programme and requires the employer to establish, maintain, record and report on the system of occupational measurements.

The Department of Mineral Resources and Energy issued a directive requiring that the dust concentration levels at the operator’s cab position on continuous mining machines be monitored.

This directive was issued to determine the effectiveness of engineering controls (water sprays, scrubber systems, ventilation controls, etc.) implemented to reduce the dust emission levels created by continuous mining machines.

This monitoring strategy can also be utilised for determining the effectiveness of engineering control measures at tipping points, transfer points, crushing plants, etc.

In the early 1900, asbestos was viewed as the wonder mineral due to its diverse applications and low cost.

Asbestos was used in any thinkable product from flowerboxes, pots, roof sheeting, prefabricated buildings, insulation on boilers and furnaces, heaters, seals, fire resistant materials, sound proofing, vehicle brake pads and shoes, general insulation, water storage tanks, pipes and so the list goes on.

The health risks associated with asbestos only became apparent long after this product was used in residential and industrial applications and by that time, for some people exposed to asbestos, it was too late and the silent killer had struck in all spheres of society, from the innocent child playing on the playgrounds next to the asbestos waste dumps to the town residents driving on the dirt roads used by the mine transport vehicles to take the asbestos bales to the railway siding.

Asbestos took no hostages, and it was too late to stop this monster.

The use of asbestos was phased out from the early 1970s and it became illegal to mine, produce or manufacture asbestos containing products during the course of the late 1990s.

The sad truth of asbestos is that because of its prolific abundance many people that have never worked with or lived in an asbestos mining town are developing asbestos related illnesses by being exposed to asbestos containing products.

The impact on society and health management systems are still to peak well into the future.

Due to the impact that asbestos has on society the Asbestos Regulations were promulgated under the Occupational Health and Safety Act and this act prescribes very stringent guidelines for the identification, control and disposal of any asbestos containing materials.

Therefore, all employers are required to take heed of the prescribed regulations to ensure that no employee is exposed to asbestos containing materials in their working environment, the company supplied residential homes, their children going to the company school with prefabricated classrooms or the community centres with asbestos roof sheeting.

Lead is a highly poisonous heavy metal that affects numerous parts of the human body.

The target organs for lead poisoning are the reproductive system, kidneys, heart, bone marrow and the central nervous system. Lead poisoning can also cause blood (anaemia), brain disorders and miscarriages in pregnant women.

Lead poisoning symptoms include abdominal pains, confusion, headache, anaemia, irritability, insomnia, delirium, cognitive deficits, tremors, hallucinations, convulsions, male reproductive problems and in severe cases seizures, coma, and death.

As with asbestos, due to the impact that lead has on society the Lead Regulations were promulgated under the Occupational Health and Safety Act and this act prescribes very stringent guidelines for the identification, use, control and disposal of any lead containing materials.

Therefore, all workplaces where lead is produced, processed, used, handled or stored in a form in which it can be inhaled, ingested or absorbed by any person in that workplace, are required to take heed of the prescribed regulations to ensure that no employee is exposed to lead containing materials in their working environment.