High-energy threshold (1,500 joules)

The research-based line above which a serious injury is the most likely outcome of contact.

  1. Below about 500 joulesA first-aid injury
  2. Between 500 and 1,500 joulesMedical treatment or lost time
  3. Above about 1,500 joulesA serious injury or fatality
Above about 1,500 joules, a serious injury or fatality becomes the most likely outcome.

The figure comes from Hallowell’s analysis of injury outcomes against the energy involved. Crews do not calculate it; they learn which situations are almost always above it.

Related terms

High-energy hazard
A hazard whose energy, if released, is enough to kill or cause life-altering injury.
STKY (Stuff That Kills You)
The plain-language name for the high-energy hazards on a job.
SIF (serious injury or fatality)
The outcomes energy-based safety exists to prevent.