While having the right filter for the job is an essential part of setting up your Respiratory Protective Equipment (RPE) solution, maintenance is necessary to ensure continuous protection. Once your filter is in place, how do you know when to replace it?

Get to Know Your Hazard.

Respiratory protective equipment filters are a crucial part of your RPE solution, in trapping smokes, particulates, chemicals, vapours aerosols, mists, gases and any other contaminants from the air before they reach the breathing zone. Not only do you need to know the type of hazard to choose the correct RPE filter type, you also need to be aware of the concentration of contaminants and other environmental factors affecting their longevity. (You can view the Anchor Safety range of filters here.)

What Factors Affect the Service Life of a Filter?

Exertion levels and frequency of use – breathing faster means that more contaminants are drawn into the filter at a faster rate.

Environmental temperature and humidity – warmer conditions can have a thermal effect on contaminants. Studies suggest that a 10 degree rise in temperature can reduce filter life by 10%, while humidity over 85% can reduce it by 50%.

Type of filter material – manufacturer’s filter specifications should detail the expected lifespan according to the active material used. Number and concentration of contaminants – Multiple contaminants may reduce service life.

Dust filters can become blocked and make it hard to breath, while gas/vapour filters have a limited life after which the contaminant will pass straight through, and the filter will offer no protection.

Developing a Bespoke Change Schedule

Because there are so many variables at play in filter lifespan, employers should develop their own change schedule taking all the above into account. Using a consultant to do this can be accurate, particularly when there is more than one contaminant present, but expensive. For single contaminant situations there are complex mathematical formulae which can also be used, however these are less accurate.

Developing a Bespoke Change Schedule

1. It is a good idea to mark the filter with the date that the packaging was opened and with an in-house expiry date. Do not use a filter which has passed its expiry date.
2. Filters should be changed before the contaminant can be smelled or tasted and before the filter life indicated in your own risk assessment
3. Change dust filters if they are damaged or visibly contaminated
4. Change dust filters if they become harder to breathe through
5. Change gas/vapour filters (Capacity 1) at least every two days or as instructed by the manufacturer; but every day if the filter is used for protection against either a carcinogen, or potential carcinogen or a respiratory sensitiser or substance that may cause allergy or asthma symptoms or breathing difficulties if inhaled
6. Change gas/vapour filters (Capacity 2) at least once a week or as instructed by the manufacturer.
7. Change gas/vapour filters (Capacity 3 and TM/TH type) as instructed by the manufacturer.

Advanced technology to take the guesswork out of safety:

Filter replacement doesn’t have to be this complicated. The Drager Xplore has advanced sensor technology which not only recognises the correct filter and provides the correct airflow, but also displays particulate filter saturation levels clearly. This solution engineers the risk out of filter replacement and ensures that while complete safety is maintained, no wastage occurs by replacing too soon.