Heat stress: NIOSH criteria
CHST written lesson, 9 min read. CHST Domain 2: Emergency Preparedness, Incident Investigation, and Response
AI-drafted from the cited rules and fact-checked against them. Study aid, not site-specific safety advice. The official rule controls.
What you'll learn
- Distinguish heat stress, heat strain and acclimatization
- Tell the RAL from the REL and name who each protects
- Calculate indoor and outdoor WBGT from field readings
- Rank engineering and administrative controls for hot work
- Describe the medical monitoring and surveillance steps NIOSH recommends
What this lesson covers
This lesson explains how NIOSH frames occupational heat stress: the difference between heat stress and heat strain, which limit applies to which worker, how WBGT is calculated, and which controls come first. These are the points the exam tests and the ones that drive real decisions on a hot job.
This lesson is included with a pass
Written lessons come with every CHST pass, along with the video lessons, the question bank, mocks and the tutor. $80 per exam or $143 for all three, for 180 days.
Try the free heat illness prevention and first response practice questions