Activities Involving Compressed and Liquefied Gases

Activities Involving Compressed and Liquefied Gases

Hazards:

The hazards associated with compressed and liquefied gases derive from:

1. The properties of the gases themselves which may be toxic or corrosive, irritant, flammable, oxidising, cryogenic or otherwise dangerous agents;
2. The explosion potential or stored energy of the containing cylinder as a pressure vessel;
3. The musculo-skeletal trauma injuries of the containing cylinder being manually handled.

Risk Factors:

·         The health hazards include asphyxiation , corrosive or toxic effects arise from the release or leakage of compressed or liquefied gases from cylinders, from experimental apparatus especially that with temporary piping or connections, and from over-pressurisation and rupturing of apparatus

·         Similar risk factors exist where flammable gases are released or leak from cylinders or apparatus in the vicinity of ignition sources;

·         Health risks and fire and explosion are aggravated if cylinders are housed or used in poorly ventilated or confined locations;

·         Fire risks are aggravated if oil, grease or other combustible materials are allowed to come into contact with oxygen cylinder valves, regulators or piping;

·         Gas cylinders may rupture if exposed to high temperatures from flames or heating devices or if cylinders are dropped or fall against other objects;

·         Musculo-skeletal or other trauma injuries result from the lifting or transporting of cylinders without adequate mechanical lifting aids.

Persons at Special Risk:

Employees receiving, despatching or moving large gas cylinders.

Risk Control Measures:

1. Cylinders should be stored in a well ventilated but weather-protected area, preferably in the open air, secured upright so that incompatible types (toxics, flammables, oxidants and corrosives) are separated by distance or structural fire-resisting partitions.
2. Cylinders in store and those being moved should be fitted with valve protection guards and the cylinder valves should be tightly closed.
3. A wheeled trolley or other suitable device should be used to move or transport all cylinders except for small ‘lecture bottle’ and pressurised aerosol containers. The cylinders should be secured in the trolley by chain or straps.
4. When in use in any work area cylinders should be restrained upright in a trolley against a fixed bench or wall.
5. Cylinders should only be used in a well-ventilated work area; cylinders of toxic gases should be placed in the fume hood if practicable.
6. Use the smallest cylinder consistent with the activity or process.
7. Compressed permanent gas cylinders should be used only with an appropriate pressure reducing regulator which should be maintained and serviced according to the manufacturers recommendations.
8. Enclosed experimental apparatus used with compressed gases should be pressure and leak tested before the process gas is introduced.
9. Personal protective clothing including stout gloves and safety footwear should be worn by staff handling or transporting large cylinders; persons using gas cylinders should wear personal protective clothing appropriate to the hazard of the gas.
10. The cylinder valve should be tightly closed at all times when the cylinder is not in actual use and even when connected to any actual apparatus.
11. After use when the cylinder is empty it should be returned to the store as soon as practicable, by contacting BOC
12. Check the identity of the gas before use by reference to the cylinder label; do not rely on the cylinder colour code.

Health Surveillance:

No special requirements

Exclusions:

This assessment may not be adequate for work with cylinders containing gases with an occupational exposure standard or maximum exposure limit of 2ppm or less; cylinders containing carcinogenic gases; acetylene; hydrogen fluoride; pyrophoric gases; liquid oxygen or the use of combustible, flammable or toxic gases in apparatus where the pressure x volume product is 200 bar Litres or more.