On July 2, 2024, the Occupational Safety and Health Administration (OSHA) released its proposed standard 29 Code of Federal Regulations 1910.148: “Heat Injury and Illness Prevention.”
The proposed standard will apply to employers in general industry, construction, maritime, and agriculture sectors for work performed indoors and outdoors that would result in employee exposure at or above the “initial heat trigger.” The “initial heat trigger” is a value defined as either a National Weather Service (NWS) heat index of 80°F or a wet bulb globe temperature (WBGT) at or above the National Institute for Occupational Safety and Health (NIOSH) Recommended Alert Limit (RAL). The proposed standard also includes a “high heat trigger” defined as either an NWS heat index of 90°F or a WBGT at or above the NIOSH Recommended Exposure Limit (REL).
The heat index is a calculated “feels like” temperature that considers air temperature and relative humidity to estimate the potential for biological heat stress. The heat index does not consider exposure to radiant energy (direct sunlight, hot equipment surfaces, etc.) or air movement. The WBGT is a function of four factors—air temperature, relative humidity, air movement, and solar/radiant energy—that are used to estimate the potential for biological heat stress. These two indices measure environmental temperatures that may cause heat stress and alert employers to proactively implement measures that minimize the potential for heat-related illness and injuries.
NIOSH’s heat-stress guidance can be found in its publication Criteria for a Recommended Standard: Occupational Exposure to Heat and Hot Environments. This document defines the RAL as a recommended heat stress limit for unacclimatized workers. Conversely, the REL is a limit to protect acclimatized workers. Acclimatization is the human body’s ability to better adapt and tolerate heat stress conditions given routine exposure over time. Employers must also consider the type (difficulty) of work performed by workers, personal protective equipment worn, and other factors that may increase the metabolic heat generated by the worker.
The main requirement of OSHA’s proposed standard is that employers will have to develop a site-specific Heat Illness and Injury Prevention Plan (HIIPP) which includes a heat monitoring plan, application of heat injury-related precautions like hydration and acclimatization, periodic HIIPP reviews and updates, and a development of a heat emergency plan. Additional provisions—such as more breaks, an observation/buddy system to monitor workers for signs of heat illness, and training—would apply at the “high heat trigger.”
Many employers already have heat illness prevention plans that include many of the elements proposed by OSHA. However, impacted employers may want to consider re-evaluating heat stress measurements and programs for their workplaces as the nation navigates summertime heat advisories to determine whether existing programs are adequate according to the requirements of OSHA’s proposal.
Employers will have 120 days to comment on the Proposed Standard as of the notice in the Federal Register. Once comments are filed, OSHA will review them and publish a final standard, likely by year end. Employers would then have 150 days to come into compliance with the final rule.
EnSafe is uniquely qualified to assist impacted companies with our experienced and knowledgeable staff of Certified Industrial Hygienists and Certified Safety Professionals to perform heat stress evaluations using WBGT, train employees on heat-related injury/illness, and develop written programs. Contact us today and let us support you in creating a safer work environment!