Maryland Heat Stress Standard Plan — COMAR 09.12.32 (Effective Sept 30, 2024)
The new Maryland heat stress plan required of every MD employer with employees exposed to heat index ≥80°F. Covers BOTH indoor and outdoor work. Built to COMAR 09.12.32 effective September 30, 2024. Includes acclimatization, water provision (32 oz/hr), shade access, high-heat procedures, emergency response, and annual training.
When this template is required
Required of every Maryland employer with employees exposed to a heat index at or above 80°F. Effective September 30, 2024. Applies to BOTH indoor and outdoor work. Heat index ≥80°F triggers the written plan, monitoring, and basic protections; ≥90°F triggers high-heat procedures. Exemptions: emergency operations, incidental exposure <15 minutes per hour, mechanically-ventilated spaces keeping heat index <80°F.
Why this template
Newest US heat standard — effective Sept 30, 2024
Maryland's heat stress standard is one of the newest US state heat mandates. Many MD employers have not yet developed compliant plans. The template addresses the current standard.
BOTH indoor and outdoor coverage
Unlike California (separate outdoor §3395 and indoor §3396 standards), Maryland combines both into one rule. Simpler structure for MD employers. The plan handles both contexts in one document.
32 oz/hr water requirement
MOSH explicitly specifies at least 32 ounces of drinking water per hour per exposed employee. Higher than some other states. The plan documents the water provision procedure.
14-day acclimatization for returning employees
Employees returning after 7+ consecutive days off must be acclimatized over up to 14 days. Newly-exposed employees: same up-to-14-day acclimatization. The plan includes the acclimatization schedule (gradual exposure increase, observation, written tracking).
What you receive
- Maryland Heat Stress Plan (Word .docx) — COMAR 09.12.32 aligned
- Heat index monitoring procedure (multiple methods)
- Acclimatization procedure (5-14 days for new/returning)
- Water provision procedure (32 oz/hr per employee)
- Shade access procedure (or alternative cooling)
- High-heat procedures (≥90°F)
- Emergency response procedure
- Annual training outline (English + Spanish)
- Training records (1-year retention)
- Bilingual employee notification
- MOSH inspection-readiness checklist
How you get it
This document is written and reviewed against the standard it cites, and it is ready now. The download link is emailed as soon as your payment clears.
Revisions included — if something about your operation changes what the document should say, reply to the delivery email and we will amend it.
Who buys this
- Maryland construction contractors (outdoor work)
- Maryland agriculture (effective for all MD agriculture)
- Maryland landscaping, tree care, lawn care
- Maryland warehousing and logistics (especially older buildings)
- Maryland food processing and commercial kitchens
- Maryland foundries, manufacturing with heat-generating processes
- Maryland delivery and transportation
- Maryland event and hospitality services
Frequently asked
When does Maryland's heat standard apply?
Whenever employees are exposed to a heat index at or above 80°F in their work area — indoor OR outdoor. The heat index combines temperature and humidity to reflect 'apparent temperature.' Exemptions: emergency operations and essential services protecting life and property; incidental exposure when employee is not required to work more than 15 consecutive minutes per hour at heat index ≥80°F; buildings/structures/vehicles with mechanical ventilation maintaining heat index <80°F.
How do we measure heat index?
MOSH allows three methods: (1) Direct measurement of temperature and humidity (using a thermometer and hygrometer, then heat index chart or formula); (2) Local weather data from National Weather Service or similar recognized sources; (3) NIOSH Heat Safety Tool app (CDC-developed). The plan documents the measurement method chosen and the threshold action levels.
What's the acclimatization requirement?
Employees who are newly exposed to heat OR returning after 7+ consecutive days of absence must be provided acclimatization over a period of up to 14 days. Acclimatization includes: gradually increasing exposure time over 5-14 days, with a maximum 20% increase each day; OR following another structured schedule meeting MOSH requirements. Close monitoring of acclimatizing employees through observation and/or communication. Written acclimatization schedule required.
What are 'high heat' procedures?
When heat index reaches or exceeds 90°F: (1) Rest periods following MOSH table (typically 10 min/2 hrs at 90-100°F; 15 min/hr above 100°F) OR NIOSH recommendations OR equivalent alternative; (2) Monitoring of exposed employees for signs of heat-related illness (phone/radio check-ins, buddy system, or other effective method); (3) Emergency response readiness. The plan documents the 90°F high-heat procedures.
Is this similar to OSHA's proposed federal heat rule?
OSHA has a proposed federal heat illness rule (proposed July 2024) that resembles Maryland's structure — 80°F trigger, 90°F high-heat, acclimatization, water, rest, shade. Maryland's rule is final and effective; OSHA's federal rule is still in proposal stage. The MD plan is current; the federal rule may add additional requirements once finalized (likely 2026-2027). The plan can be adapted to federal requirements when they finalize.