Oxy-acetylene equipment uses a mixture of oxygen and acetylene gas to produce a flame hot enough to cut steel. The equipment involves pressurised gas cylinders, regulators, flashback arrestors, hoses, and a cutting torch. Incorrect use, damaged equipment, or failure to follow safe procedures can result in fires, explosions, severe burns, and toxic fume exposure. Only trained and competent operatives should handle oxy-acetylene equipment on construction sites.
Key Hazards
Explosion from flashback travelling into cylinders or leaking gas connections
Severe burns from the cutting flame, molten metal, and hot slag
Fire from sparks and hot slag landing on combustible materials nearby
Oxygen enrichment of clothing creating a severe flash fire risk
Control Measures
Ensure only trained and competent operators use oxy-acetylene cutting equipment on site.
Inspect all cylinders, hoses, regulators, and flashback arrestors before each use.
Ensure flashback arrestors are fitted to both the oxygen and acetylene regulators.
Store oxygen and acetylene cylinders upright, secured, and separated by at least three metres.
Open cylinder valves slowly and no more than one full turn for acetylene cylinders.
Purge each hose individually before lighting the torch to remove any gas mixture.
Obtain a hot works permit and clear all combustibles within 10 metres before starting.
Never use oil or grease on oxygen equipment because it can cause spontaneous ignition.
Close cylinder valves and bleed hoses when the equipment is not in use or left unattended.
Emergency / Rescue
If a hose catches fire, close the cylinder valves immediately if safe to do so. If a cylinder is involved in a fire, evacuate the area to at least 100 metres and call 999. Do not attempt to move burning cylinders.
Remember
Flashback arrestors must be fitted to both regulators and checked before every use.
Acetylene is explosive when mixed with air and leaks must be taken extremely seriously.
Never use oil or grease on any oxygen fitting because oxygen causes oil to ignite spontaneously.
Store oxygen and acetylene cylinders at least three metres apart or with a fireproof barrier.
Purge each hose individually before lighting to prevent explosive gas mixtures forming.
If a cylinder is involved in a fire, evacuate at least 100 metres and let the fire brigade handle it.
Applicable Legislation: Dangerous Substances and Explosive Atmospheres Regulations 2002 · PUWER 1998 · Regulatory Reform (Fire Safety) Order 2005 · BCGA Codes of Practice