Hot work isn't a minor risk category. Between 2017 and 2021, NFPA tracked an average of 3,396 structure fires per year caused by welding, cutting, grinding, and other spark-producing operations. The resulting losses — 19 deaths, 120 injuries, and $292 million in property damage annually — make it one of the most measurable and preventable fire hazards in commercial construction.
The Scale of the Problem
Between 2017 and 2021, NFPA recorded an average of 3,396 structure fires per year caused by hot work — resulting in 19 civilian deaths, 120 injuries, and $292 million in property damage annually. Welding torches are the most common equipment involved.
Leading Causes
Two factors account for the majority of hot work fires: heat sources too close to combustibles and cutting or welding too close to combustible material. Together, these account for 59% of fires, 78% of deaths, and 40% of property damage. These are failures of fire watch, not failures of welding technique.
Why This Matters for Documentation
Every one of these fires triggers an investigation. Investigators ask the same question: was a fire watch maintained? Paper logs that were filled out after the fact, or never filled out at all, are the most common gap they find. The documentation standard is shifting from "did someone sign a form" to "can you prove a watcher was physically present."