The precautions that stop a soldering or hot-works task starting a fire on site.
Hot work such as soldering, grinding or using a hot-air tool can ignite nearby material during the task or leave smouldering that develops later. Assess the work and consider a method without flame, heat or sparks. Where hot work remains necessary, follow the site’s controls and permit arrangements.
- Plan and permit. On many sites hot works need a permit that records the precautions and the time limits, so check whether one is required before you start.
- Clear the area. Remove combustible materials from around the work, or where they cannot be moved, cover and protect them with suitable fire-resistant material.
- Mind hidden voids. Be alert to what is behind the surface you are heating, because heat can travel through pipes and into wall and floor voids and ignite dust or timber out of sight.
- Protect with a heat mat. Use a heat-resistant mat or guard between the flame and any surface that could scorch or catch.
- Prepare for a fire. Keep suitable extinguishing equipment available and know the alarm and escape arrangements. Only a trained person should attempt to tackle a small fire when it is safe and the site plan permits; withdraw if it cannot safely be controlled.
- Use the minimum heat. Use the right tool and no more heat than the job needs, and never leave a lit torch unattended.
- Plan the watch before starting. HSE construction guidance calls for a continuous fire watch for at least one hour after hot work stops, with another check two hours after completion. Inspect affected adjacent areas and concealed spaces as well as the joint itself. Higher risks may need longer monitoring; follow the assessment and permit conditions.
Heat can affect areas you cannot see from the joint. A completed solder connection does not end the fire precautions: arrange the watch, later checks and handover before the task begins. Any temporary change to fire detection must be authorised and managed under the site’s fire arrangements, with protection restored as required by that plan.
Storing and handling LPG cylinders
The usual propane blowlamp cylinder supplies vapour and must be kept upright, secured against falling. Laying it on its side can allow liquid LPG to reach the outlet or relief arrangements, producing a much larger volume of flammable vapour if released. Use the cylinder and appliance only in their specified orientation; this guidance is for the vapour-supply cylinders used with the torch.
Store and use them in a well-ventilated area, clear of drains (the gas is heavier than air and can collect in them) and away from heat and other ignition sources. Do not store or use them in an unventilated cabin or other enclosed space, where a leak can build up into an explosive atmosphere.