Respiratory protective equipment
Respiratory protective equipment in demolition overview
Respiratory protective equipment (RPE) can be subdivided into two categories-respirators (or face masks), which filter and clean the air, and breathing apparatus, which supplies breathable air. Respirators should not be worn in air which is dangerous to health, including oxygen-deficient atmospheres. They are available in several different forms but the common ones are:
- filtering half-mask often called disposable respirator – made of the filtering material. It covers the nose and mouth and removes respirable size dust particles. It is normally replaced after 8-10 hours of use. It offers protection against some vapours and gases.
- half-mask respirator – made of rubber or plastic and covering the nose and mouth. Air is drawn through a replaceable filter cartridge. It can be used for vapours, gasses or dust but it is very important that the correct filter is used (a dust filter will not filter vapours)
- full-face mask respirator – similar to the half-mask type covers the eyes with a visor
- powered respirator – a battery-operated fan delivering air through a filter to the face mask, hood, helmet or visor
- self-contained breathing apparatus – where air is supplied from compressed air in a cylinder and forms a completely sealed system
- fresh air hose apparatus – fresh air is delivered through a hose to a sealed face mask from an uncontaminated source. The air may be delivered by the wearer, by natural breathing or mechanically by a fan
The selection of appropriate RPE and correct filters for particular hazardous substances is best done by a competent specialist person. There are several important technical standards which must be considerd during the selection process. RPE must either be CE marked or HSE approved. HSE approval ceased in 1995 but such approved equipment may still be used. Other standards include the minimum protection factor (APF). The CE mark does not indicate that the equipment is suitable for a particular hazard. The following information will be needed before a selection of suitable RPE can be made:
- details of the hazardous substance, in particular whether it is a gas, vapour or dust or a combination of all three
- Presence of a beard or other facial hair which could prevent a good leak-free fit ( a simple test to see whether the fit is tight or not is to close off the air supply breath in and hold your breath. The respirator should collapse onto the face. It should then be possible to check to see if there is a leak);
- the size and shape of the face of the wearer and physical fitness;
- compatibility with other personal protective equipment, such as ear defenders;
- the nature of the work and agility and mobility required;
Respiratory filter and mask replacement
Filters and masks should be replaced at the intervals recommended by the supplier or when taste or smell is detected by the wearer. To 50% of all RPE used does not offer the wearer the level of protection assumed, usually because it was not fitted correctly.
The COSHH Approved Code of Practice states that ” Employers should ensure that the selected face piece is of the right size and can correctly fit each wearer.
For a tight-fitting face piece, the initial selection should include fit testing to ensure the wearer has the correct device. Also, employers must ensure that whoever carries out the fit testing is competent to do so.
The British Safety Industry Federation (working with the HSE) has developed “FIT2FIT”, an accreditation scheme for people performing face piece fit testing. An HSE document Fit Testing of respiratory protective equipment face pieces provides more detail on fit testing methods.
The HSE uses the term “face piece” and defines this to mean a full-face mask, a half-face mask, or a filtering face piece/disposable mask Fit2Fit standards are based on the HSE document.
Fit testing is needed when RPE is used as a control measure not when it is worn by choice for comfort. Fit testing should be repeated if the shape of the face of the wearer changes for any reason, such as weight loss or gain. Re-testing is recommended to check that the face piece remains suitable and that the wearer is taking care to wear and remove the mark correctly. a two-year cycle has been suggested, and a one year re-test is suggested for work with asbestos.
Fit testing can be qualitive or quantitative. Qualitative testing involves a simple pass or fail based on whether the user can taste or smell a harmless aerosol or odour through the RPE. Qualitative testing is only appropriate for disposable or half-facemasks. A quantitative fit test may use a laboratory test chamber or a portable fit test device, and produces a numerical fit factor measure.
The British Safety Industry website provides details of accredited Fit2Fit training providers. The results of fit tests should be recorded . Fit tests records must be made available to the HSE on request, and to the employees who wear RPE. RPE should be checked every time that it is used to make sure it has not been damaged and is being worn correctly.
Filtering face piece (FFP3) device
A filtering face piece (FFP3) device is a mask which is certified to the PPE Directive. It provides a high level of filtering capability and face fit. It can be supplied with an exhale valve so that it can be worn comfortably over a fairly long period of time.
It will provide an effective barrier to both droplets and fine aerosols and is the type recommended particularly for people in the healthcare sector dealing with symptomatic patients undergoing treatment where aerosols are likely to be generated.
All RPE should be examined at least once a month except for disposable respirators. A record of the inspection should be kept for at least 5 years. There should be a routine cleaning system in place and proper storage arrangements.