RAMS and method statement for hot works

Hot works cause a large share of construction and building fires, and the reason is nearly always the same: heat or a spark reached something combustible, and no one was watching when it took hold an hour later. A risk assessment and method statement for hot works is therefore built around two controls above all others, the permit and the fire watch. This guide sets out what a hot works RAMS should cover on a UK site, whether the task is welding steel, disc cutting, grinding, brazing pipework or torch on felt roofing.

What a RAMS for hot works needs to cover

Be specific about the heat producing task and where it happens. State the type of hot work, welding, cutting, grinding, brazing, soldering, blow torch or bitumen boiler, the exact location, and what is nearby that could catch, from timber and insulation to fuel, dust and the building fabric itself. A weld in an open steel yard is a different risk from cutting inside a finished building or torch on felting a roof over an occupied space, and the document and the permit should reflect the real task.

The main hazards of hot works

• Fire from sparks, hot slag, flame or radiated heat reaching combustible materials or voids.
• Delayed ignition, where smouldering starts during the work but only becomes a fire after the team has left.
• Fume and gases, including welding fume and manganese, needing extraction and respiratory protection.
• Compressed gas cylinders, oxygen and acetylene, with risks of flashback, leaks and cylinder damage.
• Explosive or flammable atmospheres, particularly in confined spaces, tanks or where solvents are present.
• Burns and hot metal to the operator and to anyone nearby.
• Arc eye and radiation from arc welding, affecting the welder and passers by.
• Electric shock from arc welding equipment, leads and damaged insulation.

The control measures a reviewer expects

Each control should map to a hazard above, and a reviewer looks first for the permit and the fire watch.

• A hot works permit issued before work starts, time limited, and closed out only after the final fire check.
• Combustibles cleared or protected, moved back a safe distance or covered with fire resistant blankets, and voids and gaps sealed.
• Fire extinguishers to hand, the right type for the risk, with the operator trained to use them.
• A trained fire watch during the work and for at least 60 minutes after, with a final check before the permit is closed.
• Gas cylinder controls: flashback arrestors on oxygen and fuel lines, leak checks, hoses in good order, cylinders upright and secured.
• Fume control: local exhaust ventilation or on tool extraction, and respiratory protection where needed.
• Screens and eye protection for arc work to protect the welder and others from arc eye.
• Timing control: no hot works in the last part of the working day, so the fire watch period is completed before the site is left.
• Atmosphere testing for any hot work in a confined space, tank or area that may hold flammable gas or vapour.

The method statement sequence for hot works

1. Assess the task and issue the hot works permit, confirming the location, the fire watch and the controls.
2. Clear or protect combustibles, seal voids and gaps, and set up fire resistant screens or blankets.
3. Position the correct fire extinguishers and brief the fire watch on their role during and after the work.
4. Check the equipment: flashback arrestors, hoses, leads and insulation, and leak check gas connections.
5. Carry out the hot work with fume extraction, eye protection and screens in place, keeping the fire watch alert.
6. Stop the work in good time before the end of the shift so the fire watch period can be completed.
7. Continue the fire watch for at least 60 minutes, then carry out a final check of the area and any adjacent voids.
8. Close the permit only once the area is confirmed cool and safe.

Where hot works RAMS usually get rejected

• No hot works permit system referenced, so there is no formal check that controls are in place.
• No fire watch, or a fire watch that ends the moment the work does, ignoring delayed ignition.
• Combustibles and voids not addressed, so a spark has somewhere to take hold.
• Gas cylinder controls missing, with no mention of flashback arrestors or leak checks.
• No timing control, allowing hot works right before the site closes.
• Confined space or flammable atmosphere not tested before hot work in tanks, ducts or basements.

Frequently asked questions

What is a hot works permit?

A hot works permit is a formal, time-limited authorisation confirming that the fire controls are in place before any welding, cutting, grinding or other heat producing work starts. It names the work, the location and the fire watch, and it is closed out only after the final fire check.

How long must the fire watch continue after hot works?

The fire watch runs throughout the work and for at least 60 minutes after it finishes, with a final check of the area before the permit is closed. This is because heat and hot slag can cause a delayed fire that only takes hold after the work has stopped.

Do I need flashback arrestors on oxy-acetylene?

Yes. Flashback arrestors should be fitted to both the oxygen and the fuel gas lines to stop a flame travelling back into the hose or cylinder. Hoses, regulators and connections are leak checked before use and the cylinders kept upright and secured.

Is this legal advice?

No. This is a plain-English working summary to support site teams. For the detail see the Regulatory Reform (Fire Safety) Order 2005, HSE guidance on welding and hot work, and your insurer's hot work conditions.

Related guides: permit to work for construction, RAMS for demolition, COSHH assessment for construction, and the fire safety on construction sites guide.