Respiratory protection in the mining sector
In the depths of the earth, even today, miners work under harsh conditions. During their 12-hour shifts, they can be exposed to a range of airborne contaminants, including crystalline silica, asbestos, diesel, particulate matter and wielding fumes under hot stifling conditions. Respiratory illnesses attributed to mining include: COPD, silicosis, coal workers pneumoconiosis (CWP), mixed dust pneumoconiosis, metal fume fever and lung cancer. Supporting site management to ensure worker’s exposures are below occupational exposure limits, are occupational hygienists. I spoke to Brett Young, a certified occupational hygienist with over 25 years of regulatory, petroleum and mining experience. He is one of several people within a large Australian organisation responsible for an operational workforce of 25,000 spread across iron ore, coal, uranium and rare earths. Whilst the safety hazards associated with mining are well known, chronic respiratory diseases such as CWP and COPD have re-emerged. Workplace health and safety legislation and a commitment from industry to implement this legislation, has seen a reduction in deaths in the mining sector. However, no fatalities are acceptable and everyone has a right to work in a safe and healthy workplace over their career. Brett says,
“The health and safety of our workforce is our priority, it’s embedded into our culture, central to our sustainability. It’s an expectation that comes from our CEO and all of our senior leadership team”.
With respect to respiratory protection, the contrast to many Australian healthcare workplaces, could not be more different. Quantitative fit testing (using a Portacount, TSI Inc) occurs annually for work groups assigned to wear respiratory protective equipment like the underground teams. Men are expected to be cleanly shaven to ensure a good seal. Respiratory protection is selected based on the individual and the hazard including gases, vapours, dusts, fumes or microorganisms. On the ground observational audits called field leadership are conducted regularly to verify compliance and effectiveness of controls. Non-compliances are corrected and reviewed for sustainability. No fit testing spells lock out for operational staff from the work environment because the risks are too great. Site management has a no-nonsense attitude to this, it’s a hazardous environment with quantifiable risks and unknowns that demand this level of vigilance.
The respiratory precautions for staff are part of an overarching respiratory protection program. The respiratory protective equipment is only one component that includes oversight from a program administrator, selection of respiratory protective equipment based on airborne contaminants, secured supply, training, fit testing, maintenance, storage and record keeping as stipulated under Australian Standard 1715: 2019. To Brett, the Australian standards are not documents gathering dust on a shelf but enacted within a safety and health management system.
Brett’s attention to detail is impressive matched by a compendium of knowledge and hands-on experience. He rattles off the sizes of respirable particles noting that the 0.3 micron fraction is most problematic; unpacks the nuances of the P1, P2 and P3 filters including their efficiency, full and half-face reusable types, describes the pros and cons of the powered respirators from loose fitting devices like the Versaflo (3M) suitable for cutting and grinding, to the closer fitting Cleanspace Halo (Cleanspace Healthcare), an on-demand device that kicks in to support up to 230L/minute of air flow when working heavily. In the repertoire also, is the self-contained breathing apparatus used by emergency response teams, again highlighting the risks of an unforgiving environment that allows no margin for error.
Brett advised, that similar to petroleum or mining, selecting the correct respiratory protection for healthcare workers during these unprecedented times is imperative. Workers need to know that the PPE provided and worn will protect them. The seal of any respirator is crucial he says, with the bridge of the nose being particularly problematic. Fit testing is crucial but the real benefit is attained during one-on-one or small group training.
“I may not see these guys for another 12 months, so I need to make sure they know how important this is and how to use and look after their equipment. These particles are not visible to the naked eye, they will follow the path of least resistance which means that the seal around the face must be tight and workers need to understand and ensure that”.
Brett’s advice is that respiratory protection equipment (RPE) training should cover:
- the airborne hazard(s) workers are exposed to
- how their RPE will protect them and any limitations
- the importance of removing facial hair from the seal for tight fitting RPE
- how to correctly don the respirator and remove it
- how to clean, maintain and store their RPE in the case of re-usable types
- how to conduct a daily qualitative fit check
- quantitative fit testing to confirm the respirator achieves the protection factor through a series of tests to simulate work tasks.
Care of the powered and re-usable elastomeric respirators is the responsibility of the individual. During the training, they are taught how to disassemble their RPE, wash it in soap and water and reassemble for re-use. The organisation has rationalised use of the P2/N95 respirator to ensure supplies remain available for specific tasks and are not depleted from the healthcare industry.
When asked about risk controls for an infectious disease, Brett is unequivocal and in a matter of fact way says, “Hygienists would always advocate for a P2/N95 respirator for an aerosolised infectious disease or microorganism risk” recognising that the “infectious dose is unknown”. One wonders how differently things would be for healthcare workers if an occupational hygienist or occupational physician had been on a guideline committee.
The mining and petroleum industry do not take short-cuts with respect to workplace safety. They have invested in a health and safety program for “as long as the Australian Standards have been around” which is implemented, enforced and supported by skilled specialists with an obsessive attention to detail. Safety for workers in high-risk industries does not happen by luck.