Understanding OSHA's Heat Index Trigger Levels: 80°F vs 90°F Explained

Two Triggers, Different Rules

OSHA uses a two-tiered approach to heat safety.

Trigger 1: 80°F Heat Index

At this level, "basic" precautions are required. This includes providing water, access to shade, and training. It is the baseline for "Heat Alert" status.

Trigger 2: 90°F Heat Index (High Heat)

At 90°F, "High Heat Procedures" kick in. This is critical. You must actively monitor employees, enforce paid rest breaks (e.g., 10 min every 2 hours), and ensure effective communication.