Breathing Compressed Air

It should be clearly understood that any employer asking an employee to breathe from a compressed air supply must ensure compliance with the Control of Substances Hazardous to Health (COSHH) Regulations 2002. The regulations provide an approved code of practice and guidance issued by the UK Health and Safety Executive and has a special legal status.

Failure to manage this risk can lead to both immediate and long term health issues such as carbon monoxide poisoning, industrial asthma or chronic obstructive pulmonary disease (COPD).

It should be clearly understood that any employer asking an employee to breathe from a compressed air supply must ensure compliance with the Control of Substances Hazardous to Health (COSHH) Regulations 2002. The regulations provide an approved code of practice and guidance issued by the UK Health and Safety Executive and has a special legal status.

The quality of compressed air used in breathing apparatus is specified in the European Standard EN12021:2014 “Respiratory protective devices – Compressed Air for breathing apparatus.” It is vital that the quality of compressed air used in respiratory applications is in accordance with the required standards to prevent risk to human health and corporate reputation.

The standard specifies that in all circumstances all contaminants shall be kept to levels below the national occupational exposure limits as defined by the Health and Safety Executive (EH40). The standard applies to self-contained compressed air breathing apparatus used above and under water (SCUBA). It also applies to systems supplying breathing air via an airline, escape devices and systems supplying synthetic air.

Requirements are specified in the standard for permissible levels of oxygen, lubricants, odour, taste, carbon dioxide, carbon monoxide and water content in compressed breathing air. The levels are summarised in the table above.

The requirements stipulate that there should be no free liquid water visible in the breathing air supply. Air used in breathing air supplies is also required to have a dewpoint low enough to prevent condensation and freezing. When the breathing air is used or stored in an area where the ambient temperature is known the pressure dewpoint has to be at least 5 Deg C below the envisaged lowest temperature. Generally, in cases where the lowest temperature cannot be predicted the pressure dewpoint is specified not to exceed -11 Deg C.

The maximum permissible water content of air at atmospheric pressure is also specified and summarised as follows;

• Air @ nominal pressure 40-200 bar, maximum water content is 50 mg / m3
• Air @ nominal pressure > 200 bar, maximum water content is 35 mg / m3

The standard also states that the maximum water content of compressed air used to fill 200 or 300 bar g cylinders should not exceed 25 mg/m 3.

Safewell provides a complete process for evaluation and implementation of solutions to purify compressed air in accordance with the prescribed quality standards. We specify a full range of compressed air purification equipment and integrate these costs effectively to provide a complete solution taking into account factors such as energy efficiency, lifecycle maintenance and cost of ownership.

Products are designed and built to exceed Breathing air quality in compliance with all relevant international standards, including Pharmacopée Européenne; DIN EN 12021; DIN EN ISO 7396-1; BS4275; ANSI/CGA G.7.1; Z180, 1 M85; AS2299-1979; NZL5813.

Contamination in compressed air used for breathing is a serious health risk. The quality of compressed air used in breathing apparatus is specified in the European Standard EN12021:2014 “Respiratory protective devices – Compressed Air for breathing apparatus.”

It is vital that the quality of compressed air used in respiratory applications is in accordance with the required standards to prevent risk to human health and corporate reputation. The requirements detailed in the Standard are summarised as in the table above.

The only way to check that your air supply is fit for breathing is by regular testing. The volume flow and the quality of the compressed breathing air supply should be tested at least every 3 months or whenever a mobile compressor is moved as the intake air is now being drawn in from a new location.

A detailed air quality test record sheet should be completed and reviewed by a responsible person to assess whether the air quality is fit for purpose. The air quality test report should be reviewed in combination with the compressor and air purifier service and maintenance records to provide a complete assessment of the breathing air installation.

Any defects in the equipment or test results should be noted and the equipment should be suitably labelled to record test status. Any defects should be remedied before the equipment is used again and a further air test carried out to ensure that the breathing air supplied is now safe. All test records should be retained like other business records.

The Control of Substances Hazardous to Health (COSHH) Regulations 2002 (SI 2002/2677) 6th Edition confirms that the exposure of employees to substances hazardous to health should be prevented, or where this is not reasonably practicable, adequately controlled.

The regulations identify the maximum exposure limits for a defined list of contaminants which may be present in the working environment. All exposure limits, both short term and long term are now identified by the term “workplace exposure limit” or WEL for short.

The EH40 ‘Occupational Exposure Limits’ is published annually for reference and are legally enforceable. COSHH Code of Practice L5 6th edition, clause 180 specifies the frequency of examination and testing in relation to compressed breathing air. This states that the quality of air supplied to a breathing apparatus should be tested based on a detailed risk assessment considering quality of the safety barrier and the lifecycle maintenance requirements. Clause 190 covers respiratory protective equipment.

In the case of mobile compressed breathing air systems, it also states that the employer should ensure that the quality of air supplied by the compressor is not compromised by nearby contaminants.

Under COSHH the employer must assess risk to employee health of exposure to all substances hazardous to health, including those from processes and germs and has a duty of care to control exposure in all uses by site and process-specific methods.

If you need help to reach this standard of air quality, please contact us and we can survey your site, rent or sell you purification equipment or provide a bespoke solution. It's really simple and we help clients every day so just ask.