'Five W's' of workplace exposure to hazardous substances

In this blog Mary Cameron, occupational hygiene team leader, discusses the 'five w's' of workplace exposure to hazardous substances:

• Who is affected?
• What employers must do
• When should employers act?
• Where to find guidance
• Why SOCOTEC plays a key role in COSHH compliance?

Who is affected? 

Anyone who works with hazardous substances is at risk. The degree of risk is determined by the likelihood of exposure, duration and frequency of exposure and how much harm the hazardous substance may cause if exposure occurs. It is important to understand the cause and route of exposure and how to implement a suitable strategy to prevent or control it. This may sound straightforward but understanding workplace exposure and control can often be very complex and unclear.  But here in lies the expertise of an occupational hygienist whose role involves identifying, assessing and controlling workplace exposures.  With cases of work-related disease showing startling numbers even in recent years, the focus on worker protection is of ever-growing importance. Guidance and initiatives from worker health protection bodies are available to help tackle this critical problem.

An occupational hygienist acts as a sort of workplace ‘detective’ - we investigate and solve. Part of a typical on-site survey for airborne hazardous substances exposure involves monitoring the personal exposure to that substance via inhalation. The worker is fitted with a sampling pump which draws air through the sampling media placed within their breathing zone. The results represent the worker’s level of exposure (for that day, in those circumstances), with more frequent sampling giving a better estimate of typical exposure.  As well as providing results from exposure monitoring, the occupational hygienist assesses the workplace and exposure controls using observation, inquisition and their professional judgement.

What employers must do

The Control of Substances Hazardous to Health Regulations (COSHH) 2002 (as amended) states under Regulation 7 (prevention or control of exposure to substances hazardous to health) three points which determine ‘adequate control’.  Two of these points are that exposure to the hazardous substance should not exceed the workplace exposure limit (WEL) and in the case of a substance which is carcinogenic, mutagenic or a sensitiser exposure must be reduced to ‘as low a level as is reasonably practicable’.  The third point being that the principles of good practice for the control of exposure to hazardous substances are met (COSHH Schedule 2A).  The WEL is not a defined line between ‘safe’ and ‘unsafe’.  Although WEL compliance is required, emphasis is heightened on control of exposure.  Our occupational hygienists sample the level of worker exposure but also focus on assessing the employer’s exposure control strategy, any shortcomings and advising on improvements where needed.  This may involve redesigning the process to minimise hazardous substances release or choosing more effective control options.

Occupational lung disease causes significant debilitating ill-health and an estimated 13,000 deaths per year.  Research also shows that about 36,000 people who worked in 2016 have breathing or lung problems they thought were caused or made worse by work, and there are an estimated 14,000 new cases of breathing or lung problems caused or made worse by work each year. Employers must ask what they are required to do to prevent occupational lung disease, or any other work-related ill-health.  As stated under COSHH regulations, the employer must carry out a suitable and sufficient risk assessment of the work which may expose employees to hazardous substances. On the basis of this risk assessment the employer must ensure that the exposure of his employees to substances hazardous to health is either prevented or, where this is not reasonably practicable, adequately controlled. COSHH Regulation 10 covers the requirement, should the risk assessment deem necessary, for the employer to monitor workplace exposure to ensure adequate control. COSHH Regulation 9 requires control measures in place to be regularly maintained, examined and tested to ensure continued adequacy.  An occupational hygienist can aid the employer in complying with these regulations by assessing the personal exposure to hazardous substances and examining the control measures in place (such as local exhaust ventilation testing) to assess its performance.

When should employers act?

Employers have a duty to protect workers, this means that they must assess the risks and take all necessary steps to prevent exposure. I was recently involved in a visit to a sandstone quarry monitoring for the worker’s exposure to silica dust. Breathing in respirable crystalline silica (RCS) can lead to the development of lung disease such as silicosis, COPD and even lung cancer in cases where exposure is heavy and prolonged. Sandstone can contain 70% to 90% crystalline silica content. So the employer required an assessment of his worker’s RCS exposure levels and advice on how to implement adequate control measures. I assessed the site including the stone processing facilities and gave suitable and realistic exposure control recommendations such as at-source extraction systems, foam/wet spraying onto the stone, plant halt should personnel entry be required and RPE use in the cases of unavoidable exposure (i.e. in-plant maintenance or repair work).

During my visit I also discovered a fitter’s workshop, where anywhere from 2 to 8 hours a day of metal fabrication work is undertaken (grinding, welding, and cutting) without the aid of local or general ventilation. The worker concerned was being exposed to potentially significant levels of welding fume (airborne metals and metal oxides) not to mention by-products such as carbon monoxide, nitrogen oxides, ozone, build- up of inert gases and even phosgene if welding on metal items which have been degreased.  Health effects from exposure to welding fume can include metal fume fever, siderosis and systemic poisoning. I suggested immediate actions to reduce exposure (LEV installation and suitable RPE in the interim) and worked with the employer on producing a risk assessment and risk management plan for this task.  In this case the initial site visit to the quarry was over shadowed by the glaring issue of RCS exposure.  But it is important as an occupational hygienist to ensure the site is thoroughly assessed for all potential significant exposure risks.

Where to find guidance 

In most circumstances, the occupational hygienist is hired in for a one-day assessment.  But the employer is liable for worker protection year-round.  Thankfully, there is a plethora of guidance available from worker health protection bodies such as the Health and Safety Executive (HSE) and British Occupational Hygiene Society (BOHS). In fact, the BOHS has undertaken an initiative named ‘Breathe Freely’ which is aimed at reducing occupational lung disease in the UK. The original initiative focuses on controlling exposure to prevent occupational lung disease in the construction sector and the more recently launched second initiative focuses on the manufacturing sector.  With the risks from working in construction being greater than for any other sector, focus is given to preventing exposure to hazardous substances generated in everyday construction tasks.  Arguably the most well-known hazardous substance created during construction work is silica dust, but many others may be encountered such as isocyanates, solder fume and wood dusts.  The manufacturing-based initiative emphasises exposure prevention to welding fume. Many helpful tools are available on the Breathe Freely website including toolkits, factsheets, guides and access to training courses.

An occupational hygienist is an important player in the fight against workplace-caused ill-health.  But the person who is the most able to make a positive change and instigate real improvement, is you, the employer, and you, the employee.  It is as important now as it ever was to understand the health risks and how to work together to improve working conditions through suitable and effective control or prevention measures.  SOCOTEC’s highly qualified and passionate team of occupational hygienists can provide essential services aiding in COSHH compliance and worker health protection.

Why SOCOTEC plays a key role in COSHH compliance

Anyone who works with hazardous substances is at risk. The risk in certain sectors may be higher than others but the duty to prevent or control that risk is required by all employers. The COSHH regulations state ‘adequate control’ of exposure to hazardous substances to be achieved by not just keeping exposure to below the workplace exposure limit but also applying good practice for the control of exposure. SOCOTEC’s occupational hygienists can help the employer in their COSHH compliance programme by assessing the worker’s exposure to hazardous substances and also by undertaking examination of control measures in place to ensure continued performance or recommend improvements. Occupational hygienists are there to assess, advise and improve upon workplace hazards. The employer also has available to them a wide range of support from worker health protection bodies such as the HSE and BOHS.