Check out the courses we offer
Knowledge Base » Health and Safety » What is Hot Work?

What is Hot Work?

Last updated on 20th April 2023

Anyone doing work that involves open flames, extreme temperatures or work that generates extreme heat or sparks needs to be knowledgeable about fire safety and how best to protect themselves and others from accident or injury at work.

The Fire Protection Association (FPA) suggests that from the latest available statistics looking at fires in the construction industry, of 218 total fires, around 44 (or just over 20%) had been directly caused by hot work.

Fires need three components to start: a source of ignition, a fuel source and oxygen. Hot work that is undertaken in or near buildings provides the ideal conditions for the fire triangle. Fire and extreme heat can cause serious injury; therefore, it is important that anyone who is required to do hot work does so as safely as possible.

Welding is hot work

What is hot work?

Hot work is any work that requires the application of heat or that generates extreme heat. This could be directly, such as from an open flame, or from anything that will create a spark, such as cutting metal with an angle grinder, or something that generates extremely high temperatures, such as using metal pipes as a conductor.

Hot work examples:

  • Welding.
  • Soldering.
  • Cutting and grinding.
  • Brazing.
  • Flame cutting.
  • Thawing pipes.

Hot work can be dangerous and, where possible, it is often safer to look for alternative methods. However, hot work is often necessary, especially for certain construction processes or remedial works, as well as for fabricating items, such as for metal forming that is standard in automotive manufacturing.

What are the dangers of hot work?

By definition, hot work is dangerous because it involves extreme temperatures and flames or sparks that can cause injury or fires.

Hot work is routinely used in construction and building projects as part of the construction process or to maintain or repair parts of an existing building. Stray sparks or extreme heat can cause fires to ignite within buildings or on building sites.

The dangers that hot work can present are twofold; firstly, there is danger to self (the person working or those around them) and secondly, there is danger to the environment (the area that they are working in).

Danger to self:

  • Burns and injuries relating to hot flame or sparks.
  • Injuries from accidental fire.
  • Smoke or fume inhalation.
  • Electrical hazards.

Danger to environment:

  • Potential to cause fires (from sparks hitting combustible materials, or pipes or electrics becoming overheated or from naked flames themselves).
  • Damage associated with burns or fires (items melting, destruction of property etc.).
  • Potential for explosion (if explosive material is present, even at low levels).

Most hot work fires are caused because safe working procedures are not followed, hot work is done in an area not designed for this purpose, or because the risk assessment failed to pick up on combustible materials being present.

In addition to the danger of illness, injury or even death associated with hot work and the potential to destroy property, there is also the financial burden that comes with accidents or incidents.

This includes:

  • Time off work for anyone injured to recover.
  • Lost wages.
  • Works being suspended for investigations.
  • Arduous insurance claims.
  • Loss of productivity and continuity on site.
Hot work can cause burns

Hot work control measures

Risk management is needed to prevent any procedure that has risks associated with it from becoming a hazard. It is not possible to remove all risks which is why they need to be controlled and managed by competent people. This lessens the chances of work-related accidents, injuries, instances of ill health and accidental fires occurring.

Hot work is commonplace in certain industries or for particular projects, and the risks associated with it will need to be measured and controlled in the same way they would be for other risks, such as working at height or use of chemicals.

This includes:

  • Full training to be given to anyone doing hot work.
  • Correct PPE to be provided and used.
  • All tools and machinery required for hot work to be fit for purpose and regularly inspected.
  • HSE legislation to be followed.

The most important aspect of ensuring that hot work is undertaken safely is that a competent person must conduct a thorough risk assessment.

This risk assessment needs to be specific to hot work and should look for certain risk factors such as:

  • Risk of fire from sparks or heat being conducted via metal pipes.
  • Presence of combustible materials (including stored ones, obvious ones or hidden ones).
  • Any openings in the building structure that will require covering with non-combustible sheeting.
  • Type of insulation used in the building.
  • Electrical hazards from using hot work equipment.
  • Exposure to radiation (some work such as welding can involve harmful UV or infrared light that can damage eyes and skin).
  • Exposure to fumes (hot work can produce fumes that can cause significant respiratory problems and damage to eyes).
  • Burns and skin injuries from sparks, hot surfaces, tools or debris created by hot work.

The hazards identified and the control measures that need to be put in place will need to relate to the specific job, the area that hot work will be done in, who is taking part and any external variables that need to be considered (such as the weather).

Sometimes hot work will only be done in one location, such as a car body shop, so the risks will be easier to identify and manage. The people undertaking the hot work and the environmental and structural factors that affect it will remain fairly constant.

In the construction industry, the risks will need to be managed for each individual site – with repair work or ‘live sites’ likely proving to be the most hazardous for hot work. These types of jobs should be managed very carefully if including hot work is going to be unavoidable.

What is a hot work permit?

A hot work permit is used as a safeguarding measure. It is a signed document that details the work that is being carried out, when and by who, as well as control measures that are in place.

An informed hot work permit should protect the person, or people, undertaking the work, other people that are on site and the site or building itself. They are written up and signed off by an authorised person who understands the risks involved and how to mitigate them.

This should ideally be someone with knowledge of health and safety, who is trained to do a risk assessment and who has experience of fire prevention and fire safety protocols.

Hot work permits are generally considered necessary for ‘temporary’ hot works. In services where hot work is routinely used, such as fabrication shops, the work area is normally designed with this in mind. However, risk assessments are still required and fire safety advice needs to be followed, as well as hot work only being completed by a competent and trained worker.

A hot work permit is needed for the duration of the project where hot work is being undertaken. Having the permit should mean that you are compliant with legal or legislative requirements, and in many cases they are also required for insurance purposes. The permits cannot be reused.

The hot work permit will need to be informed by a thorough risk assessment and will need to be site specific. It will state that risks have been controlled or minimised (such as removing flammable liquids or materials, sweepings floors to remove dust or debris and using non-combustible sheets to cover gaps) as well as giving advice on fire safety and who to call in an emergency (999).

It will also need to outline basic information including:

  • The site where the hot work is being done.
  • The name of the person who is doing it (and possibly whether they are employed, self-employed or an external contractor).
  • The date and times that the permit will be valid.
  • The designated fire watcher.
  • A brief description of the work being done.

The permit will need to be signed by all relevant parties before the work starts and be signed off at the end by an authorised person once work has been finished without incident.

Work being done after a permit has been completed

Managing the hot work permit

Site managers should visit the area where hot work is taking place to ensure that the information detailed in the permit is still relevant and that guidance is being followed.

It is also recommended that contractors take pictures (if practical) of the area before they start any hot work.

Any hot work on site should be:

  • Authorised.
  • Monitored.
  • Documented (in writing).

You will need to think about three key areas of the site when you start to think about managing risks from hot work:

1. Which areas, if any, are designated for hot work (designed specifically with this in mind).

2. Which areas are not designated for hot work (this is where the permit will be needed).

3. Which areas are prohibited (because they contain highly flammable materials or chemicals or are unsafe for this type of activity and risks cannot be managed).

Your hot work permit is a control measure that is often also required to validate your insurance. Once you have conducted a risk assessment and written up a hot work permit, it is important that the work is managed correctly and continually assessed.

Having a hot work permit alone, will not eliminate the hazards that hot work introduces if it is not implemented and the advice in the permit not followed.

1. Decide if hot work is unavoidable (could a safe working procedure be used?).

2. A qualified and competent individual must draft the hot work permit.

3. Carry out a risk assessment which informs your hot work permit.

4. Use only trained workers (or contractors) – check their credentials, insurance and that they are fully trained for the task in hand.

5. Ensure workers are familiar with the contents of the hot work permit and understand the risks and controls required.

6. Designate fire watchers (they will assess the area and surrounding areas for fire during the works and for a minimum of 60 minutes afterwards).

7. Only provide and use equipment and PPE that is fit for purpose and safe.

8. Spot-check the work area to check for compliance (before, during and after the hot work).

9. A 60-minute fire watch is recommended after work is completed (because fires do not always ignite immediately – some can be slow burn).

10. Sign off the hot work permit only once work is safely completed and the final fire watch has ended.

Even with all of the control measures in place, there is still the risk of an injury occurring or a fire being accidentally started. It is vital to ensure a qualified first-aider is on site and that everyone in the area is trained in fire safety and evacuation procedures.

It is also advisable that all workers know what to do in the event of an emergency, whether hot work is being done or not.

A hot work permit is a legal requirement under some circumstances (namely hot work within a construction or maintenance project).

It will also be expected as part of a fire safety plan by enforcement bodies such as:

  • Fire safety officer from the local authority.
  • HSE (Health and Safety Executive), which is a governing body for health and safety and fire safety in Britain.
Fire safety officer doing safety checks

Representatives from both the local authority or HSE can conduct pre-arranged or spot checks on site to assess compliance with the law and legislation around fire safety or health and safety at work. As part of this they may request to see permits for any hot work that has been done.

If they find a site is not compliant or that risks are not being adequately controlled, they may:

  • Give advice (formally or informally).
  • Request records (to review, copy or remove).
  • Serve improvement notices.
  • Conduct individual or joint investigations (especially after a significant breach is discovered or a serious incident occurs).

They also have the power to close down a site, or to prosecute in instances of serious negligence.

It is necessary to keep any hot work permits on file in case they are requested during an inspection.

Hot work will never be without its risks, but these risks can be managed. With proper training, the correct tools and reliable equipment, the chances of a serious incident or accident occurring can be significantly reduced. By using the correct procedures and documentation, you will be able to prove that you are being compliant and that the safety of all workers on site during hot work is being prioritised.

Welding Awareness

Welding Awareness

Just £20

Study online and gain a full CPD certificate posted out to you the very next working day.

Take a look at this course


About the author

Vicky Miller

Vicky Miller

Vicky has a BA Hons Degree in Professional Writing. She has spent several years creating B2B content and writing informative articles and online guides for clients within the fields of sustainability, corporate social responsibility, recruitment, education and training. Outside of work she enjoys yoga, world cinema and listening to fiction podcasts.



Similar posts