What is Hot Work?
The HSE defines hot work as the: ‘use of
open fires, flames and work involving the
application of heat by means of tools or
equipment.’ Common types of hot work
include:
• Welding, brazing, and soldering.
• Grinding and cutting.
• Thawing pipes.
• The use of open flames, blow-
lamps, and torches.
• Using bitumen and tar boilers.
• The use of hot air blowers and lead heaters.
This is not an exhaustive list, but it does include the most common examples of hot work.
All hot work can pose significant health and safety risks when carried out without proper control.
Common Hazards of Hot Work
Hot work can present numerous types of hazards to workers and the environment around
them. However, the most common and significant risk of hot work is fire and explosions.
Without the proper safety procedures, all types of hot work can easily ignite a fire.
Fire hazards posed by hot work include:
• Flying sparks. This is the main risk posed by hot work. Sparks can easily get trapped
in cracks, pipes, gaps, holes, and other small openings, where it will potentially
smoulder and start a fire.
• Flammable swarf, molten metals, slag, cinder, and filings. The debris and residue
that hot work creates are often highly combustible and/or hot.
• Heat conduction when working on pipes. Hot work can cause a pipe to heat up
substantially and this heat can easily transfer through the process of conduction to
another, potentially flammable surface and cause a fire.
• Hot surfaces. If you don’t properly remove flammable materials or substances from
the area before you start hot work, they could come into contact with a surface that
has become hot during the work and easily start a fire.
• Explosive atmospheres. In certain environments, there may be vapors or gases in
the air that are highly combustible and could ignite when exposed to hot work.
Similarly, the hot work could generate fumes that create an explosive atmosphere.
It’s important to note that the hazards associated with hot work will depend on the
specific work activity and the environment in which it is being undertaken.
Hot Work Control Measures
A variety of industries may require hot work in their premises as part of routine work activities,
though it is also frequently carried out as part of contractual work. However, no matter the
reason for, or duration of, the hot work being undertaken, it’s essential that the hazards have
been assessed and appropriate controls have been enforced.
As previously mentioned, employers have a legal duty to ensure that risks in their workplace
are assessed, controlled and monitored so that their employees remain safe from harm,
including the risks from hot work activities. Control methods must be selected in line with the
hierarchy of control which is outlined below:
1. Elimination – Elimination means to avoid carrying out hot work activities. This can
be done through a number of ways. For example, if a tank requires hot work to repair
it, completely replacing the tank instead of repairing it.
2. Substitution – The second step in the hierarchy involves substituting for a safer or
less hazardous alternative, such as using cold cutting or cold repair methods rather
than hot work.
3. Engineering controls – This involves using physical solutions to reduce risks, such
as using general mechanical ventilation (ducted air with fans) or local exhaust
ventilation (to remove fumes from the point of origin).
4. Administrative controls – This involves altering the way the activity is undertaken to
make it safer, e.g. the use of safe systems of work, permit-to-work systems and training.
5. Personal Protective Equipment (PPE) – The final stage of the hierarchy of control
is the use of PPE to reduce any residual risks. Examples of PPE include respiratory
protective equipment (RPE), hearing protection, eye protection and anti-static
clothing and boots. PPE must only ever be used as a last resort and only when all
other stages in the hierarchy of control have been considered.
Lists of materials and accessories commonly used for hot works:
• Personal Protective Equipment (PPE)
o Welding helmet with appropriate shade o Welding jacket
lens
o Safety glasses
o Fire-resistant gloves o Steel-toed boots
• Welding Equipment
o Welding machine (arc welder, MIG welder, o Welding rods or wires
TIG welder, etc.)
o Welding torch
o Gas tanks (for gas welding and cutting) o Welding curtains
• Cutting Equipment
o Oxy-fuel cutting torch
o Cutting tips
o Cutting gas (usually acetylene)
o Oxygen tank
• Brazing and Soldering Equipment
o Torch
o Brazing or soldering rods
o Flux
• Other Tools and Accessories
o Wire brushes o Clamps
o Grinders
o Fire extinguisher
o Ventilation system
