Avelair Compressed Air Systems: Breathing air quality testing

Breathing air quality testing

The quality of breathing air is vital in terms of Health and Safety. The British Standard for BS EN / 12021 defines the maximum contaminant parameters for Breathing Air and states that tests for volume flow and quality should be carried out at least once a month. Our Breathing Air Quality Testing confirms the level of oil, water, carbon monoxide, carbon dioxide, and volumetric flow fully in accordance with the latest requirements for air purity as described in BS EN / 12021. On completion of each test a Breathing Air Quality Test Report is issued indicating the results. We offer a full Breathing Air Quality advisory service.

To what standard should the air be?

The British Standard for Breathing Air is BS EN / 12021 which states the criteria for air purity shall be the following:

Oxygen
20% to 23% by volume (dry air).
Carbon Monoxide
Not more than 5ml/m3.
Carbon dioxide
Not more than 500 ppm.
Oil mist
Not more than 0.5 ppm.
Odour / taste
Without significant odour or taste.
Water liquid
There shall be no free water.
Water vapour
Air up to 40 bar for compressed air line breathing apparatus should have a pressure dew point sufficiently low to prevent condensation and freezing. Where the apparatus is used and stored at a known temperature, the pressure dew point should be at least 5 deg C below the likely lowest temperature. Where the conditions of usage and storage of the compressed air supply is not known, the pressure dew point should not exceed -11 deg C. For air between 40 bar and 200 bar, the water content should not exceed 50mg/m3. For air above 200 bar, the water content should not exceed 35mg/m3.

Frequently asked questions

Is a combination of coalescing and activated carbon filters sufficient for a breathing air outlet point?

Yes, the Avelair SMF and AK filters are excellent for this application. However you must ensure that the intake air to the compressor is not contaminated with carbon monoxide or carbon dioxide, the dew point meets the water vapour criteria, the system is properly maintained, and regular tests are carried out at the breathing air outlets.

Where is it likely that the intake air will be contaminated?

When the compressor intake is taken from or near main roads, car parks, loading bays, vehicle workshops, airports, process works, city centres etc.

How will we know if the air is contaminated?

You will only know if the air is contaminated by regular testing. It is a requirement under the COSHH Respiratory Protection Equipment Code of Practice and BS 4275 – 1997 that breathing air outlets points are tested for purity and flow at least once every month and more frequently in a more hazardous environment. Flow is dependent on the type and make of RPE in use. Typically maximum flow rates for demand masks are approximately 60 l/min, for constant flow masks are approximately 120 l/min, and for full suits are approximately 400 l/min.

Will breathing air at -40 deg C pressure dew point cause health problems?

No, an operator may experience a slight dryness of the throat after prolonged exposure or rigorous activity, and remember moisture is a great breeding ground for bacteria.

Request a breathing air test

Please contact Avelair for any further information.

The leading UK based manufacturer of rotary screw air compressors