Compressed air is used in many industries. Compressed air is air that is kept under pressure – higher than normal atmospheric pressure. Compressed air has many purposes, including use in pressurized gases, vehicle propulsion, railway braking systems, air guns, paintball equipment, refrigeration and energy storage. Working with compressed air can cause many illnesses, known as “decompression illness”. Symptoms include pains around the joints. This is known as Type 1 Decompression Sickness. On rare occasions the central nervous system can be affected, this is known as Type 2 Decompression Sickness. This type can be fatal. Workers may experience barotraumas; this is where there may be direct damage to air containing cavities in the body such as the nose and sinuses. One may also experience dysbaric osteonecrosis, this is a chronic condition damaging the bones and joints. Compressed air can be dangerous if it enters body orifices such as the mouth and ears. Air jets can damage the eyes. At high pressures air can penetrate the skin.
The Work in Compressed Air Regulations 1996 provides guidance on how to manage health and safety for those working in compressed air systems such as tunnels and construction work in compressed air. As well as the duties under the Health and Safety at Work etc Act 1974 being placed on all employers, the duties of the Compressed air regulations are placed on Compressed air Contractors. Because some workers in the construction industry work with compressed air, the Construction (Design and Management) Regulations 2007 also contain guidance on compressed air.
The contractor should ensure that all individuals working with compressed air are trained to do so and carry out safe systems of work. There should be adequate supervision of workers on site at all times. All plant and ancillary equipment must be of appropriate design and construction without risks. A Medical Advisor must be appointed on-site to provide occupational health advice on all aspects of work. Each employee who works in compressed air must undergo adequate medical surveillance. If it is the professional opinion of the medical advisor that an employee should refrain from work with compressed air, the employer must honor this change in work role. In the case of work undertaken at a pressure of 0.7 bar or above, facilities at the plant should include a medical lock and competent medical personal to operate this medical lock. Individuals working with a pressure of 0.7 bar or above should be supplied with a worded badge or label that contains particulars as to the nature of the work. The contractor shall ensure that individuals working in compressed air should not be subjected to pressure exceeding 3.5 bar except in an unforeseen emergency. Persons must be in good medical and physical condition, and, if they have any ailments on entering the role, the contractor should not permit them to undertake the role. There must be sufficient and suitable emergency evacuation procedures in place for persons working with compressed air. There must be suitable means of raising an alarm and maintenance thereof.