HeatGuard field guide
Outdoor work heat safety: a planning checklist
A forecast can help schedule work, but it cannot replace a workplace heat program. Prevention combines environmental monitoring with workload, clothing, acclimatization, supervision and emergency response.
01
Build controls around the work
Move demanding tasks to cooler hours where operations allow. Use engineering controls such as shade, ventilation or cooling, plus work-rest schedules, task rotation and a buddy system.
Water, rest and shade work as a system. Training should help workers recognize symptoms, report concerns and activate the emergency plan.
- Define who monitors conditions and how often.
- Provide accessible water and recovery areas.
- Document escalation steps before an emergency.
02
Acclimatization changes risk
New workers and people returning after time away can be more vulnerable. Gradual exposure helps the body adapt. A heat wave can also create new risk for experienced workers.
Supervisors should consider workload and clothing. Impermeable or protective equipment can reduce heat loss and may require a more conservative protocol.
03
Estimate versus compliance measurement
HeatGuard estimates WBGT from forecast variables. It does not use a physical globe thermometer at the jobsite and cannot capture every microclimate. Do not use it as documentation that a regulatory or contractual threshold was met.
Check federal, state and local requirements. Some jurisdictions impose specific heat rules, and requirements can change.
- Use the required calibrated instrument.
- Record readings under the workplace procedure.
- Treat symptoms as urgent even when readings look acceptable.
Primary sources
Continue planning
This guide provides environmental planning information. It is not medical advice, an emergency service, or a substitute for an applicable workplace, school, league or governing-body protocol.
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