Risk Engineering

Hot Work (Hot Work Permit)

Expert-reviewed Updated: 2026-09-01 Expert-reviewed: 2026-09-04 (Guido Hesse, Hesse Group Holding AG) Version 0.1.0

Hot work such as welding, cutting and soldering is among the most frequent fire causes in industrial plants; a formal permit procedure with a fire watch drastically reduces the risk.

Core elements of the permit procedure

Before starting: written authorisation by a responsible person, review of alternatives (cold methods), removal or covering of combustibles within at least 11 metres (35 feet), provision of extinguishing equipment and instruction of all involved.

Fire watch

During the work and for at least 60 minutes afterwards (up to several hours depending on the insurer), a fire watch monitors the work area including adjacent rooms and cavities – many fires start from smouldering pockets long after work has finished.

Insurance relevance

Many property insurers make the permit procedure a policy condition; violations can lead to reductions in indemnity. For external contractors, the procedure must be contractually enforced and controlled – a key inspection point of every risk engineering survey.

Standards and codes

  • NFPA 51B – Standard for Fire Prevention During Welding, Cutting, and Other Hot Work