Reusable respirators make use of replaceable filtration cartridges to filter hazardous substances and protect the wearer. There are various respirator filters available, each designed to filter different substances. It is important to know what is the appropriate cartridge to adequately protect employees from sustaining temporary or permanent respiratory conditions. This article shall provide information to assist in this regard.
When selecting the appropriate respiratory protection, it is important to identify the hazardous substance and how hazardous it may be that employees shall be handling. How hazardous a substance is will depend on the toxicity, chemical state, physical form, concentration and the length of exposure. Examples of potential respiratory hazards include:
- Particulates: airborne dusts, fibres, fumes, mists, smoke, and biological contaminants (bacteria, viruses, and fungi),
- vapours, and
- oxygen-deficient atmospheres.
Should one be unaware of the category into which the hazardous substance falls, a safety officer should have all the relevant safety data sheets on hand, it is necessary to contact your PPE supplier so they may direct you to the correct protection.
Filters used for specific purposes:
All filters are available in either single or twin to fit the specific respirator. In other words, you get respirators that take one filter and others that take two filters. The only filter which is not available in single is the ABEK Filter, the ABEK filter is a combination filter which can be used in environments where there are a variety of different hazards and none can be isolated. It provides protection across the board.
Filters for specific substances for example A, organic substances, are marked 1 or 2. Although both 1 and 2 protect against the same contaminants, the 2 filter filters at a higher parts per million compared to the lower parts per million for the 1 filter. Therefore providing protection against higher concentrations of vapours.
Replacing the filter, when the user starts to “taste” the hazardous substance, the filter must be changed. This differs for individuals, but filters provide approximately eight hours of use.
The maximum filtration of particulate filters vary as follows:
Pre–filters and filters which are used in combination to another filter and provide an extra level of protection when required. Pre–filters are used in environments where there is a particulate hazard as well as a gas, vapour, acid hazard. The pre–filter fits onto the main filter, which protects against the gas etc., and filters out the particulate, such as dust. This allows you to use the filter suitable for the job, while protecting against other particulates and not having to go the full combination filter route.
For further clarity and information please view our respiratory hazard directory which provides a detailed guide to all harmful substances and the appropriate filter to make use of.
Article prepared and written by Zandy van der Westhuizen – 10.07.2020