In some work areas, particularly in industrial sectors such as oil and gas, chemical, pharmaceutical and manufacturing, the ambient atmospheric air is too contaminated for operatives to breathe without risk to health. In these cases, it is common practice, and an essential duty of care, for employers to provide a breathing air system.
Within a purified compressed air supply network, it is essential to carry out air quality tests to ensure that the control measures put in place are delivering the air quality required. In the UK, EN12021 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 final decision on frequency of tests is the responsibility of the employer and needs to not only reflect local legislation but also the task and frequency of use. It should be incorporated into risk assessments and updated regularly to reflect results from ongoing breathing air tests in order to maintain a robust control system.
Standard compressed air is probably insufficient to ensure consistent breathing air quality and it is vital for all to realise that untreated compressed air is not clean. The compression of ambient air concentrates the normal contaminants already present in the air and can also introduce other constituents such as oil vapours, condensed water and bacteria that can have an immediate effect on operators’ well-being and long-term health.
It goes without saying that only competent personnel should be involved in designing breathing air systems and preparing risk assessments. To assist employers in this complex area of Health & Safety, it is recommended that managements seek the assistance of compressed air system suppliers with specific breathing air capabilities and product ranges, such as Atlas Copco, who will have competent persons trained in providing and maintaining breathing air systems.
In order to limit health risk and to comply fully with regulatory requirements it is essential that assured purity levels are achieved by the purification unit within the compressed air network. The ideal breathing air system should have the capacity to take air from any type of compressor and convert it into ultra-clean breathing quality air. It needs to combine the functions of water separation, contaminant filtration and desiccant drying of the air output.
One such unit, Atlas Copco’s BAP (breathing air purifier) range, features seven vital functions: a water separator that removes any liquid water, a bulk aerosol filter to eliminate oil and water content, a fine coalescing filter to remove even smaller particles of oil and water from the supply, plus a desiccant dryer to take out any remaining water and CO2. An activated carbon filter is included to remove gaseous impurities and a catalyst takes care of CO oxidation. Finally, a bacteria filter eliminates micro-organisms and fine particles.
This level of capability ensures the breathing air purifier complies with a wide range of standards and regulations, such as OSHA Grade D, NFPA-99, CSA Z180.1-00, CGA G7.1-1997, EN 12021, BS 4275, ISO 14971, OHSAS 18001, European Pharmacopeia and other International Breathing Standards. Such compliance guarantees a safe working environment in a wide range of applications, ranging from shot-blasting, tank cleaning, tunnelling, pharmaceutical manufacturing, spray painting, offshore/marine processes, asbestos removal, to high-pressure cylinder filling and many others.