Hot Works Permits: A Complete Guide for Site Managers

Hot works are among the leading causes of workplace fires in the UK. Welding, cutting, grinding, soldering, and any other activity that introduces a source of ignition into the workplace must be carefully controlled — and the permit to work is the primary tool for doing that.

This guide covers everything you need to know about hot works permits: what they are, what they must contain, the legal framework behind them, and the practical steps for issuing one correctly.

What counts as hot works?

Hot works is the term for any activity that generates heat, sparks, or open flame that could ignite flammable or combustible materials. Common examples include:

• Welding (MIG, TIG, arc, spot)
• Oxy-fuel cutting and welding
• Grinding and disc cutting
• Soldering and brazing
• Use of a blowtorch or heat gun
• Torch-applied roofing or waterproofing membranes
• Any operation generating sparks near flammable materials

If the activity introduces an ignition source and there is any possibility of flammable materials being present, a hot works permit is required.

The legal basis for hot works permits

No single piece of UK legislation uses the phrase "hot works permit," but the requirement to have a safe system of work for hot works is well established in law:

• Health and Safety at Work Act 1974 — requires employers to ensure, so far as is reasonably practicable, the health, safety and welfare of all employees and others affected by the work
• Management of Health and Safety at Work Regulations 1999 — requires employers to assess and control risks from work activities
• Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) — requires control of risks from fire and explosion where flammable substances may be present
• Regulatory Reform (Fire Safety) Order 2005 — requires the "responsible person" to take general fire precautions and manage fire risk, including from hot works contractors

What must a hot works permit include?

A compliant hot works permit should cover all of the following:

1. Permit identification

A unique permit number, the date and time of issue, and the permit validity period (date and time the permit expires).

2. Work description and location

A clear description of the specific work being carried out, the exact location, and the name of the contractor and permit holder. The more specific this is, the better — vague descriptions like "welding work" provide no protection if something goes wrong.

3. Identified hazards

All foreseeable fire and other hazards associated with the specific job. For a typical hot works permit, this should include at minimum:

4. Control measures

The specific steps taken to control each hazard. Standard hot works controls include:

5. PPE requirements

For hot works, PPE should typically include flame-retardant clothing, welding visor or goggles appropriate to the task, leather welding gauntlets, safety footwear, and respiratory protection if fume risk is identified.

6. Pre-authorisation safety checks

A checklist of specific confirmations the permit issuer must verify before signing off — for example, confirming the fire watch person has been briefed, or that the fire alarm has been checked.

7. Emergency procedure

What to do in the event of a fire or other emergency: how to raise the alarm, who to contact, and where to assemble.

8. Authorisation and acknowledgement signatures

The permit issuer's signature confirming all controls are in place, and the permit holder's signature confirming they have read and accepted all conditions.

The fire watch requirement

One of the most commonly neglected aspects of hot works safety is the post-work fire watch. Fires do not always start during the hot work itself — smouldering materials can ignite minutes or even hours after work has finished.

A fire watch person must be:

• Dedicated to that role — not also carrying out or assisting with the hot work
• Briefed on what to look for and what to do if they see signs of smouldering
• Equipped with a serviceable fire extinguisher appropriate to the risks present
• Present continuously — not stepping away "just for a moment"

Common mistakes to avoid

• Issuing the permit too generically. A permit that says "welding on plant" is not specific enough. Name the room, the equipment, the contractor, and the specific task.
• Not confirming controls before signing. The permit issuer must physically verify that fire extinguishers are present, flammables have been removed, and the fire watch person is ready — not just trust that the contractor has done it.
• Failing to close the permit. A permit that is issued but never formally closed provides no evidence that the work was completed safely. Closure checks must be completed and recorded.
• Using the same permit for multiple days or repeat jobs. Each instance of hot work requires its own permit. Permits are not reusable.
• No audit trail. Paper permits stored in folders are difficult to retrieve and easy to lose. If an incident occurs months later, you need to be able to produce the permit record quickly.

Download a free hot works permit template

We've produced a free Hot Works Permit to Work template in Word (.docx) format, available in both a pre-filled version (standard hazards and controls already populated) and a blank version.

We also have free templates for Excavation & Ground Works, Lifting Operations, Electrical Isolation, Working at Height, and Confined Space Entry. Visit the templates page to browse and download all types.

Beyond paper: managing hot works permits digitally

A well-designed paper permit is better than nothing. But paper has real limitations: you can't search it, you can't see at a glance what permits are currently active, and there's no guarantee the form was completed accurately or that it won't be lost.

PermitDesk generates hot works permits (and all other PTW types) in seconds using AI — describing the job in plain English and getting a complete, pre-populated permit draft in return. Permits are issued digitally, accepted by the permit holder on their phone, and stored automatically with a full timestamped audit trail.

Related reading

→ What is a permit to work? A plain-English guide

→ Working at Height Permits: WAH Regs 2005, rescue plans & harness inspection

→ Electrical Isolation Permits: lock-out tag-out, confirmed dead & AP/CP roles

→ Confined Space Entry Permits: atmospheric testing & standby person requirements

→ Excavation & Ground Works Permits: CDM 2015 & service strikes

→ Lifting Operations Permits: LOLER 1998 & Appointed Person duties

→ Browse all free permit to work templates