# COMAR 09.12.32 — State Heat Illness Prevention Standards — Temperature Triggers and Required Employer Actions

For COMAR 09.12.32, jurisdiction is Maryland; effective date is September 30, 2024; initial trigger temperature f is 80; initial trigger actions is Provide shaded areas as close to work area as practicable, open to air on at least three sides; provide cool potable drinking water; allow preventative cool-down rest periods; high heat trigger temperature f is 90, recorded from its source on 2026-08-17.

- **jurisdiction:** Maryland _(verified: appears in the quote below)_
- **regulation citation:** COMAR 09.12.32 _(verified: appears in the quote below)_
- **effective date:** September 30, 2024 _(our reading, not quoted from the source)_
- **initial trigger temperature f:** 80 _(verified: appears in the quote below)_
- **initial trigger actions:** Provide shaded areas as close to work area as practicable, open to air on at least three sides; provide cool potable drinking water; allow preventative cool-down rest periods _(our reading, not quoted from the source)_
- **high heat trigger temperature f:** 90 _(verified: appears in the quote below)_
- **high heat actions:** Minimum rest period of 10 minutes for every 2 hours worked at heat index above 90°F and below 100°F; minimum rest period of 15 minutes for every hour worked at heat index above 100°F; monitor exposed employees via phone, radio, buddy system, or other effective observation; rest periods taken in shade _(our reading, not quoted from the source)_
- **coverage scope:** Indoor and outdoor; all industries where heat index equals or exceeds 80°F; exempt: emergency operations and essential services, incidental exposure under 15 consecutive min/hr, mechanically ventilated buildings/vehicles below 80°F _(our reading, not quoted from the source)_
- **acclimatization period days:** 14 _(verified: appears in the quote below)_
- **written plan required:** Yes _(our reading, not quoted from the source)_

## What the source says

> This chapter applies to an employer with employees whose employment activities, indoor or outdoor, expose employees to a heat index in the area where the employee is working that equals or exceeds 80 degrees Fahrenheit.

## Source

- https://regs.maryland.gov/us/md/exec/comar/09.12.32.02

Last verified: 2026-08-17. Review by: 2027-08-17.
Part of [State Heat Illness Prevention Standards — Temperature Triggers and Required Employer Actions](https://referencesource.org/state-heat-illness-prevention-standards/).