Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings Rulemaking


Heat is the leading cause of death among all weather-related phenomena, and it is becoming more dangerous as 18 of the last 19 years were the hottest on record. Excessive heat can cause heat stroke and even death if not treated properly. It also exacerbates existing health problems like asthma, kidney failure, and heart disease. Workers in agriculture and construction are at the highest risk, but the problem affects all workers exposed to heat, including indoor workers without adequate climate-controlled environments. Workers of color disproportionately make up the population of employees in essential jobs who are exposed to high levels of heat, which exacerbates socioeconomic and racial inequalities in the U.S. In addition, climate change is increasing the frequency and intensity of extreme heat events, as well as increasing daily average daytime and nighttime temperatures.

About the Advance Notice

On October 27, 2021, OSHA published an Advance Notice of Proposed Rulemaking (ANPRM) for Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings in the Federal Register. With this publication, OSHA is beginning the rulemaking process to consider a heat-specific workplace standard. A standard specific to heat-related injury and illness prevention would more clearly set forth employer obligations and the measures necessary to more effectively protect employees from hazardous heat. The ultimate goal is to prevent and reduce the number of occupational injuries, illnesses, and fatalities caused by exposure to hazardous heat.

The publication of the ANPRM initiated a public comment period allowing OSHA to gather information, diverse perspectives and technical expertise on issues that might be considered in developing a heat standard. These issues include the scope of a standard, heat stress thresholds for workers across various industries, heat acclimatization planning, and heat exposure monitoring, as well as the nature, types, and effectiveness of controls that may be required as part of a standard.

The publication of this ANPRM has no impact on OSHA's current enforcement policies.

OSHA encourages members of the public to review and submit comments on the ANPRM during the public comment period. The ANPRM is available on the Federal Register web page and at www.regulations.gov, which is the Federal e-Rulemaking Portal. OSHA reviews and analyzes all material in the public rulemaking record to determine if and how it should proceed with rulemaking.

The comment period closed on January 26, 2022.

Specific Topics of Interest

OSHA is interested in obtaining additional information about the extent and nature of hazardous heat in the workplace and the nature and effectiveness of interventions and controls used to prevent heat illness. Recommendations should account for indoor and outdoor work environments and businesses of all different sizes. Specifically, OSHA seeks information, data sources, and examples on the following topics:

  • Occupational illnesses, injuries, and fatalities due to hazardous heat, including their under reporting and magnitude across geographic regions or among various industries, occupations, job tasks, or businesses of various sizes 
  • Determinants of hazardous occupational heat exposure and heat-related illness in the work place 
  • Inequalities in exposures and outcomes among workers of color and low-wage earners 
  • Structure of work and work arrangements affected by hazardous heat
  • Existing efforts on heat illness prevention, including by OSHA, states, employers, or other industry associations 
  • Heat illness prevention plans and programs
  • Engineering controls, administrative controls, and personal protective equipment 
  • Acclimatization 
  • Physiologic and exposure monitoring
  • Planning and responding to heat illness emergencies 
  • Worker training and engagement 
  • Costs, economic impacts, and benefits 
  • Impacts of climate change on hazardous heat exposure for outdoor and indoor work settings