Fuel gas processes, by their very nature, use flammable, potentially explosive gases, often in conjunction with oxygen.
The gases may be supplied in, and used from, pressurised gas cylinders and mixed in welding or cutting torches. The main hazards, therefore, are from naked flames, fire, and explosion.
Perhaps the most dangerous occurrence is a 'flashback'. This happens when a flashback in the hose travels back towards the cylinder at very high speed.
If not checked it can set fire to fuel gas in the cylinder, resulting in explosion.
Hose check valves and flashback arrestors must ALWAYS be used to prevent flashback.
Other physical hazards occur during manual handing of cylinders and the changing and fitting of regulators.
Processes such as thermic lancing, powder cutting and spraying may sometimes produce fume in significant amounts, but generally these processes give low levels of fume.
All the above hazards may be exacerbated when working in confined spaces, in hot, wet, cramped areas, or if working at height.
Workers should be aware of the potential hazards of each process and the means to avoid or control the risks.
Safety training and the adoption of safe working practices will help to minimise risk.