Breathing Air Quality Testing
If you are using compressed air as breathing air in the workplace, it is a legal requirement for UK employers to conduct breathing air quality tests to ensure the safety of their employees. The quality of air from compressors can vary substantially and it is important to ensure that the air being supplied is suitable for breathing air purposes.
In the UK, EN 12021:2104 advises that samples should be taken and analysed at least every three months, or more frequently if there has been a change in, or any concerns relating to, the production process. The required quality of breathing air must conform to defined safe limits of potential contaminant gases to ensure that the life support gas, oxygen, is of an adequate level.
Employee health and safety
Employers should ensure that wherever a compressor is located, the quality of air it supplies is not compromised by nearby contaminants. Compressed air for breathing normally originates from a compressor system installed or operating at the place of use.
Factors that can affect the quality and safety of compressor air
The compressor can draw in airborne contamination from local processes such as vehicle exhaust fumes that are not removed by standard breathing air filtration. Though the contamination may not be continuous, the pollution of the air supply can persist for hours or days.
Malfunctioning compressors, especially of the reciprocating type, can produce unsafe levels of both carbon monoxide and carbon dioxide. Faulty dryers can raise oxygen concentration levels to outside safe breathing air parameters. Air filters have a shelf life and failure can cause high levels of oil and water contamination to be present in the air.
The performance of desiccant filters is dramatically affected by operating temperature, resulting in poor quality air being supplied. Failure of aftercooling will result in air entering the filtration at too high a temperature, permitting excess levels of oil and water.
Respiratory Protection Equipment
High levels of water in breathing air may freeze within Respiratory Protection Equipment (RPE) valves. Insufficient airflow or pressure to the RPE will reduce the protection factor and potentially expose the user to contaminants.
WHAT MAINTENANCE IS REQUIRED?
Air compressors should be regularly checked and maintenance carried out according to manufacturers’ guidelines. Particularly if they are regularly moved around in different environments.