Respiratory equipment should only be used if you are not able to protect yourself in any other way. Respiratory equipment protects the lungs and the rest of the respiratory system against dust, vapours (aerosols, spray mist), steam, gases, bacteria and viruses. The guidelines in this manual do not apply to emergency masks, smoke hoods and equipment for use when oxygen is lacking.
- Respiratory equipment is the final solution
- Types of respiratory equipment
- Filter masks
- Choice of respiratory equipment
- Use, maintenance, etc.
- How long should you work with breathing equipment?
- Approval of breathing equipment
Respiratory equipment should only be used when you can not protect yourself in any other way. Other forms of protection can be assisted air, extraction, closed systems or replacement of a chemical product with one that is less harmful or harmless. If you attempt to replace one chemical product with another, you must weigh all the danger factors against each other. In some cases it is better to use a product that releases vapour for example than to use one that causes injury to the eyes and skin.
You should also consider whether to change working methods so that you can completely avoid coming into contact with hazardous chemicals or dust.
There are two different types of respiratory equipment, those with external air and those with filter masks. The filter masks are divided further into two different groups: those with turbo (assisted air) equipment and traditional filter masks.
Filter masks of the traditional type filter the air supply but you have to breathe through the filter. The turbo type of filter masks drives the air through a filter but the air comes from the surrounding environment and can be contaminated.
Traditional filter masks
Traditional filter masks can be full mask or half mask with a replaceable filter which provides protection against vapour, dust (dust filter) as well as aerosols and gases (gas filter). Filters can also be combined to protect against several things at once such as dust, vapour and aerosols (combination masks).
Finally, there are filtering face masks (paper masks) where the entire mask is thrown away when the filter is used up. There are types which protect against dust, vapour, aerosols or gases.
Face masks which are an improvement over the traditional thin paper masks for dust protection have now been developed. These masks can be used once or twice before disposal.
Filtering face masks should have an exhaled breath valve, which means less condensation in the mask, making it easier to breathe normally.
The full mask is the filter mask which gives the best protection. It is easier to adjust to different shaped faces than a half mask. It is a closer fit so there is less risk of leakage around the mask. On the other hand, there are disadvantages. They are heavier to wear and restrict vision more than the other types of mask. In use, it is a good idea to have a replaceable clear plastic film on the visor glass to prevent the glass from getting scratched, sprayed or otherwise damaged. You can get such film from mask suppliers.
Half masks are lighter and provide better vision than the full mask. On the other hand there is a greater risk of leakage. It can, however, be difficult to avoid leakage where the mask touches the face. This is particularly true if the same mask type has been chosen for use by everyone who needs one.
Filtering face masks are light and are the most comfortable. As for half masks, leakage often occurs around the edge of the mask. The best and most expensive filtering face masks have adjustable head straps, exhalation valves and sealing rings along the edge, all of which ensure a tighter fit around the face. There are cheaper filtering face masks on the market but these should not be considered personal protection but rather masks that provide more comfort. Approved filtering respiratory equipment always has a label marked EN149:2001, as well as the type, for example, FFP2 (in compliance with EU regulations).
Turbo (assisted air) equipment
Turbo equipment is a common name for all types of respiratory equipment with filters where the user does not personally have to inhale the air from the surrounding area through a filter or filters. In the case of turbo equipment, there is a fan that sucks the air through the filter, so there is no resistance to breathing for the user to overcome. Turbo equipment is available for full mask, half mask, hood, helmet or screen.
For masks with replaceable filters both with and without fans, it is essential that you do not put together any equipment consisting of different items from different manufacturers. It is the total package of equipment that is approved and classified under the protection factor in equipment regulations. Since assisted air equipment has batteries and an electric motor, it is important to ensure that equipment is explosion-proof if it is going to be used in areas where there is a risk of explosion.
External air breathing equipment
Breathing equipment with its own air supply - the air is provided by means of a compressor or a cylinder carried on your back. The compressor must have an air intake somewhere where the air is clean. This enables this type of equipment to be independent of the surrounding local air supply. Such equipment can be used with full and half masks, hoods and visors and it protects against all forms of contamination. External air breathing equipment provides better protection than both filter masks and assisted air equipment. The air used in the breathing equipment must be pure. According to Danish legislation, its inlet air must be checked at least once a year.
The air temperature should be between 15-25oC. The regulations for respiratory equipment air can be found in the Danish Maritime Authority's Technical Regulation No. 6 of 26th August 1996.
- What hazardous substances and materials are present in the air? Are there aerosols, vapours, gases, dust or combinations of these?
- Are filters available to protect against the air contaminants concerned? For example, low boiling point liquids with boiling points of less than 650C (e.g. acetone), or substances that are not readily absorbed by activated charcoal filters? How high is the concentration?
- Is work being done indoors or outdoors? If humidity is high, use a supplied-air respirator. High temperatures significantly increase evaporation rates of organic solvents.
- How poisonous are these substances? Is there a threshold value? Can the substances be smelt? If they cannot be smelt, filter respirators must not be used because how would you know that the filter is used up?
- How long will work take?
- How physically demanding is the work?
- Is the user suitable for wearing the respirator? (Beard, stubble, glasses, unusual face shape?)
- Is lack of oxygen a risk? Special the rules apply here for safety precautions and not all supplied-air respirators are suitable.
- Do special rules apply to the job? (e.g. code numbered products).
The protection factor states how many times the respiratory equipment can reduce the concentration of harmful substances inside the mask in relation to the concentration in the surrounding area. This is established by laboratory tests. So the protection factor for breathing equipment may be regarded as a factor in assessing whether or not equipment is good enough for the particular situation. On the other hand, you cannot choose respiratory equipment exclusively on the basis of its protection factor.
It can be hard to judge contaminant concentration in the air but the code numbering system for paint, etc, will help you select the right type of breathing equipment.
If for example you are going to use water-based paint indoors (Code 0-1) on a small area (< 4m2) using a paint brush or roller, no breathing gear is required. On the other hand, using a roller or paint brush on a small area (< 4m2) outdoors with paint Code 4.3 means you will need to use a gas filter mask. For larger areas, use external air equipment. The personal protection schedule available in the paint shop will show the precise equipment to be used.
- There are no filters which can protect against the chemicals in the air.
- The work is so physically taxing that breathing through a filter is difficult. Turbo equipment may be a possible option in this case.
- It is impossible to find close-fitting filter masks, for example because the wearer has a beard or wears glasses (you can find filter masks with a liner where you can insert a pair of glasses.
- If it is impossible to smell air contamination. This means you will not be able to smell when the filter has been used up and needs replacing.
- The code number means that external air breathing equipment should be used.
- That filters that protect against the types of air contaminants in question are available.
- That you can actually get the filters you need for masks or turbo equipment. There is some respiratory equipment for which you cannot get all types of filter.
- That the filters are so effective that they can protect against actual concentrations of air pollution in question.
All types of breathing equipment are accompanied by instructions for use with details of storage, cleaning, maintenance etc.
Filters should be stored in air-tight containers when they are not in use, otherwise they are liable to absorb vapour and gases during storage. The maintenance of inhalation and exhalation valves is particularly important. The integrity of masks can be tested by blocking the filter and taking a deep breath. There should be a partial vacuum in the mask lasting about 5-10 seconds while you hold your breath. If, however, the supplier recommends another type of test for integrity, use this instead.
The user should be trained in the use, maintenance and storage, etc., of the breathing equipment. Follow the manufacturer's instructions and ask your supplier if you are in any doubt.
Filter masks should not be used for longer than a total of 3 hours per working day. External and assisted air equipment should not be used for longer than a total of 6 hours per working day. And young persons under 18 may not use these for longer than a total of 4 hours per working day. Depending on the strain factor of the work and how difficult it is to breathe while working, a suitable number of breaks should be taken during the working day.
Breathing equipment purchased in EU countries must be approved (CE marked). Equipment not purchased within the EU should be of at least the same standard. Ask your supplier if specific equipment conforms to CE quality standards. The major manufacturers' products are sold in most of the world, the only difference being that the same respiratory equipment is sold in Europe with a CE stamp of approval and without it in the rest of the world.
When choosing and purchasing respiratory equipment, you should always consult your supplier.
Senior Occupational Health Consultant
Anne L. Ries
+45 3311 1833
+45 2961 8860
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