Air purifying respirators (APR’s) using replaceable vapour filters and cartridges provide respiratory protection in the workplace against certain organic vapours, gases and particles. Air purifying respirators come in a range of designs including helmet, half or full face mask or hood style depending on the level of protection required and whether eye protection is needed. Three types of APR include:
- powered APR’s which provide filtered air under positive pressure to a face mask, helmet or hood and provide high levels of respiratory protection
- non powered APR’s which require greater effort from the wearer as they have to draw air through the filter
- disposable versions which usually don’t provide eye protection and capacity varies depending on the replaceable cartridges used.
Filters and cartridges available to attach to air purifying respirators include those for filtering:
- particulate matter such as dust, mists and fumes
- chemical cartridges which provide protection against gases and vapours
- particulate and chemical cartridges combined.
As for all personal protective equipment (PPE) effectiveness can be limited by improper use or selection of the correct protection for the job. All air purifying respirators protect only as good as their seal to the face and being worn during all chemical exposure.
For workplace situations where the chemical contaminants are high or components unknown, supplied air respirators are required. Types include:
- atmosphere supplying respirators (SCBA—self contained breathing apparatus). These units provide the highest level of respiratory protection as compressed air is breathed in through a full face mask connected to a cylinder
- supplied-air respirators (SAR) supply air from a full face mask that is linked to an external air source by a hose or airline. These generally have a longer use period and high levels of protection.
Workplace solutions and adjustments
For individuals exposed to airborne chemical vapours within the workplace, an appropriate assessment of respiratory protection and workplace safety will need to be undertaken as part of the overall respiratory protection program. This may identify the need to use personal protective equipment involving respiratory protection masks with filters. Individuals with sensitivity to chemicals may require specialised assessment to determine if the use of filtered air can assist with reducing the impact of chemical exposure to health, and potentially improve work productivity and performance.
When considering exposure to chemicals the following links may be useful:
References
eMedicineHealth 2011, Personal Protective Equipment: Civilian Equipment, WebMD, Inc., online, viewed 22 February 2011, http://www.emedicinehealth.com/personal_protective_equipment/page3_em.htm.
McKay, R. T. 2011, Air purifying respiratory protection, Chemical Health & Safety, vol. 4, no. 5, viewed 22 February 2011, http://pubs.acs.org/action/showPublications?display=journals.