Hot work is any work that has the potential to ignite nearby combustible, flammable or explosive material.
Common hot work tasks include:
- Thermal or oxygen cutting
- Other related heat-producing or spark producing operations
Hot work potential hazards:
- Fire: caused by heat, molten metal, sparks or direct contact with cutting or welding flames.
- Explosions: caused by the presence of gas, liquid vapours or suspended flammable dust.
- Toxic fumes: generated directly from the hot work process or through heat decomposition of nearby material(s).
These hazards create a serious risk to workers health and safety that can lead to injury, illness and death.
For example, burns from heat radiation or contact with flames, sparks, molten metal or hot surfaces, and exposure to hazardous fumes.
Hot work processes have the potential to ignite fires that can travel beyond site boundaries. Fires may also start well after the completion of any hot work activities due to residual heat.
The Australian Standard AS/NZS 1674.1:1997 – Safety in welding and allied processes Part 1: Fire Precautions may be of benefit when identifying and controlling risks.
Any worker undertaking hot work must:
- Hold the welding qualification relevant to the task being performed; and
- Grinders, thermal or oxygen cutting or heating equipment, or other related heat-producing or spark-producing equipment must only be operated by workers who are experienced and competent in using the equipment.
Hot Work Permits
Where hot work is to be undertaken in an area other than a designated hot work zone a Hot Work Permit is to be completed. The Hot Work Permit is divided into four (4) sections:
- Details of hot work
- Risk controls to be implemented
- Verification of risk controls
- Completion of work
Designated hot work zones
A designated hot work zone may be established and authorised by the relevant manager. A hot work permit is not required to undertake hot work in a designated hot work zone.
In order for an area to be designated a hot work zone a risk assessment must be documented, and the outcomes of the risk assessment documented and retained.
Hot works in hazardous areas
A hazardous area is an area in which a flammable atmosphere is or may be expected to be present. Hot work in hazardous areas requires special precautions to be implemented before it can be undertaken.
Before undertaking hot work in a hazardous area, a Job Safety Analysis (JSA) must be developed to specify how the work will be undertaken and the risk controls that will be implemented.
General hot work safety
When undertaking any hot work, the following safety requirements must be meet:
- Identify the scope of work and the potential hazards; e.g., flammable atmospheres or generation of toxic fumes, etc.
- Monitor the atmosphere by undertaking atmospheric testing for flammable gasses before and during hot works, even in areas where a flammable atmosphere is not anticipated
- Check for hidden voids or compartments that may share the same airspace. These areas may be a hidden source of flammable vapours
- Ensure all areas are free of flammable and/or potential flammable vapours
- Ventilate, clean or ensure the vapours and/or gasses have been made inert in the space before undertaking any hot work that when heated may create an explosive atmosphere
- Ensure safe work practices are followed when undertaking hot work
- Ensure hot work permits are obtained where necessary.
Number one recommendation is to ensure any person undertaking hot work has the appropriate qualifications for the work they are undertaking.
Secondly ensure a Hot Work Permit is in place prior to the start of any hot works where required and thirdly ensure all safety precautions are in place.
If undertaking hot work onboard a vessel or in a workplace where the work is carried out in the same location and is not a designated hot work zone you can develop a generic Safe Work Method Statement (SWMS) which will cover your operations. This saves you from having to do a JSA every time!