The welding stops, the contractor packs away and the permit is signed off. A spark has already travelled through a gap into concealed combustible material. The visible work is finished, but the fire is not. A hot work permit should control a defined high-risk task from planning to safe hand-back; it is not a certificate that makes welding, cutting or grinding safe by itself.
Avoid hot work before trying to permit it
Hot work includes work that uses or generates enough heat, flame or sparks to ignite material. Welding and flame cutting are obvious examples, but grinding, brazing, soldering, torch-on roofing, heating and some hot-air tools can create the same problem. The location matters as much as the tool: sparks can travel, hot metal can fall through openings and heat can conduct into the other side of a wall, panel or vessel.
Start by asking whether the task can be removed from the area or completed cold. Bolting, mechanical cutting, prefabrication or moving the component to a designated hot-work bay may reduce the risk materially. HSE's permit guidance includes a case where cold cutting near an operating pump house and hot cutting in a safer place had been agreed, but the undocumented arrangement was not followed and flammable vapour ignited.
If hot work remains necessary, define the exact equipment or structure, location, method and time window. A generic annual permit for a workshop, contractor or job type cannot reflect today's stock, nearby process, building fabric, weather or simultaneous work.
HSE: permits to work ↗ · Related guide: contractor management checklist →
Connect the task assessment to the statutory fire risk assessment
The responsible person must carry out and regularly review a fire risk assessment for the premises. It must identify fire hazards and people at risk, reduce the risk, support emergency arrangements and address vulnerable people. Introducing hot work—or changing its place, frequency, method or surrounding materials—can make an existing assessment unsuitable.
Review and update the statutory fire risk assessment when the work introduces or materially changes the fire hazard. Where the main assessment does not contain enough task detail, complete a linked hot-work assessment and incorporate its findings into the main FRA, emergency arrangements and site controls. Do not leave the findings inside the contractor's method statement where the person controlling the premises cannot act on them.
Consider combustible construction, sandwich panels, roof voids, ducts, penetrations, stored packaging, flammable liquids and gases, dust, process releases and adjacent occupancies. Where dangerous substances could create a fire or explosion atmosphere, the assessment may also need to address DSEAR. Work on tanks, pipes or containers needs positive evidence about contents, cleaning, isolation, venting and—where relevant—atmospheric testing.
GOV.UK: workplace fire risk assessments ↗ · Fire Safety Order 2005: article 9 ↗ · Related guide: DSEAR risk assessment →
Make the permit a live control, not a signature exercise
HSE describes a permit-to-work as a documented procedure that authorises specific people to carry out specific work within a stated timeframe and records precautions based on risk assessment. It requires declarations from those authorising and doing the work, with arrangements for handover, extension and return to normal use. The permit must match the task, area and people actually present.
Name the permit issuer, person in charge, operator and fire watch. Record the equipment, boundaries, start and expiry time, isolations, precautions, emergency action, suspension triggers and hand-back checks. Cross-reference the risk assessment and any isolation, confined-space or impairment certificate. Display the permit at or near the job and brief everyone affected, including other contractors and production staff.
HSE's HSG250 guidance is centred on petroleum, chemical and allied industries, although its permit principles can help other workplaces. It is guidance, not a hot-work law or certificate. HSE is explicit that issuing a permit does not itself make the job safe: preparation, supervision and the people doing the work must implement the controls.
Prepare the area and protect what sparks can reach
Inspect the work area immediately before authorisation. Remove combustible waste, packaging, dust and movable stock. Where material cannot be removed, use suitable protection and prevent sparks or hot fragments passing underneath, behind or through it. Check both sides of walls, floors, roofs and panels. Covering what can be seen while leaving an open penetration or combustible core is weak control.
Isolate relevant fuel, gas, electrical, process and ventilation systems using a verified method. Control cylinders, hoses, leads and extraction equipment. Maintain clear escape routes, suitable alarm arrangements and appropriate firefighting equipment. If detection, suppression, compartmentation or an evacuation route is impaired, treat that as a separate change requiring authority, compensatory measures, time limits and confirmed restoration.
Stop the work if conditions depart from the assessment: a leak develops, combustible stock arrives, the wind changes, another task enters the exclusion zone, an alarm or sprinkler is isolated unexpectedly, or the person in charge changes. Do not amend a live permit informally. Suspend it, reassess the conditions and reauthorise only when controls are suitable.
Review the hot-work controls before the contractor arrives.
HR + SAFETY can help North East workplaces connect the task assessment, fire risk assessment, permit, isolations and hand-back arrangements.
Discuss a hot-work reviewKeep watch during the job and prove a safe hand-back
A competent fire watch must be able to see the affected area, recognise early signs of fire, raise the alarm and use the provided equipment without being given another task that distracts them. Monitoring may need to cover adjacent rooms, floors, voids or the opposite side of a surface—not only the arc or flame.
Continue post-work monitoring for a period determined by the assessment, construction, materials, fire spread routes, work method and applicable site or insurer requirements. There is no single period that is safe for every job. Record who will monitor, what areas they will check, the frequency or continuous period required, how they will communicate and when the area may be released.
The final signature should confirm more than 'work complete'. Check for heat, smoke, smell, smouldering material and damage; inspect concealed or adjoining areas where relevant; remove equipment safely; restore alarms, sprinklers, barriers and process isolations; account for occupants; and communicate the hand-back to the person controlling the premises. If inspection cannot rule out concealed ignition, keep the area controlled and escalate rather than closing the permit.
Hot work permit checklist for responsible persons
Premises with sleeping occupants, healthcare or care functions, difficult evacuation, vulnerable people, extensive combustible construction or serious business-continuity consequences require additional scrutiny. Consider timing the work when fewer people are exposed, increasing supervision and monitoring, protecting escape arrangements and obtaining competent fire-safety input before authorisation. These practical descriptions should not be confused with the defined Building Safety Act term 'higher-risk building'.
Legal requirements and official guidance were checked on 5 October 2026. The permit records and communicates controls; it does not replace the fire risk assessment, task assessment, competence, supervision or physical precautions.
- Confirm whether a cold method or designated hot-work area can remove the need.
- Define the exact task, location, equipment, people and authorised time window.
- Review the statutory fire risk assessment and complete a linked task assessment where needed.
- Check dangerous substances, previous contents, residues, dusts and atmospheric-test needs.
- Remove or protect combustibles, openings, voids and vulnerable adjoining areas.
- Verify process and energy isolations and record any fire-system impairment.
- Provide competent operators, supervision, fire watch, alarm access and suitable firefighting equipment.
- Coordinate simultaneous work, occupants, contractors and emergency arrangements.
- Set clear suspension conditions and prevent informal permit extensions.
- Specify and record proportionate post-work monitoring and safe hand-back.
A defensible hot-work system can answer six questions before the first spark: can the work be avoided, what can ignite, who has authority, which controls are verified, who keeps watch and who proves the area safe afterwards? If any answer is unclear, the permit is not ready to issue.
This guide provides general information for UK employers. It is not legal advice and should not replace advice based on the facts of a specific matter.