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United States · MarylandIn force

Maryland adopts indoor and outdoor heat protections

Maryland's indoor and outdoor heat-protection regulation took effect September 30, 2024. Covered work at a heat index of 80°F or above requires heat-stress protections, with additional measures under high-heat conditions.

Scope to keep in mind

The core status and scope are supported by agency guidance. The full regulation still needs review before applying detailed requirements at a workplace.

Legal status
Effective
Source check
Sep 17, 2026
Topic
Heat stress
Technical review
Jiaxi · 2026-09-23

What changed

Previous requirement

General safety obligations; no historical standalone heat standard comparison audited.

New requirement or current position

Covered indoor/outdoor work at heat index 80 F or above requires heat-stress protections, with additional high-heat measures.

Who it affects

  • Construction
  • Manufacturing
  • Outdoor work
  • Indoor work

Dates and milestones

Commencement and compliance dates can differ. Read the conditions beside each date, including any stay or local adoption requirement.

Announcement or publication
Sep 30, 2024
Recorded effective date
Sep 30, 2024
Sep 30, 2024

Covered indoor and outdoor workplaces

What this could mean for your IH program

Advisory interpretation: Track heat index with its correct measurement basis. Use the regulation for exceptions and high-heat work/rest details.

Confirm applicability with a qualified practitioner before changing your program.

Questions and qualifications

  • This entry covers the core status and scope confirmed by the agency. The full regulation has not been reviewed for detailed workplace application.

Source evidence

  1. Maryland Heat Stress

    Maryland Department of Labor / MOSH · Opening and Summary of Key Requirements

    COMAR 09.12.32 effective September 30, 2024; indoor and outdoor heat-index trigger 80 F; written plan, acclimatization, water, rest and training.

  2. Key Requirements: Maryland Heat Stress Standards

    Maryland Department of Labor / MOSH · pp.1-5

    Confirms effective date and heat-index thresholds; this is agency guidance, full regulation controls exceptions.

Related findings

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