Federal OSHA has taken a variety of steps and initiatives to address heat stress including informative webpages, a much-anticipated National Emphasis Program (NEP) they plan to launch in Spring 2022, and consideration of a permanent Heat Stress Standard through an Advanced Notice of Proposed Rulemaking (ANPRM) in October 2021.  The ANPRM closed January 2022 and OSHA received over 1,000 comments so it will be many months before a proposed rule will be published.  The NEP will focus on “high risk industries” including manufacturing and construction.  An NEP allows OSHA to direct resources to the issue including enforcement of standards.  In the case of heat stress, in lieu of a permanent Federal standard for heat stress, OSHA can and will use the General Duty Clause to cite companies for alleged violations for not protecting workers from serious injury / harm. As part of its efforts to promulgate a full standard, Federal OSHA recently established the Heat Injury and Illness Prevention Work Group of the National Advisory Committee on Occupational Safety and Health (NACOSH). The Work Group met for the first time on February 25 and was established to help NACOSH respond to OSHA’s request to provide recommendations on the agency’s heat injury and illness prevention guidance and rulemaking activities.

What is Heat Illness? Heat illness includes several medical conditions caused by overexposure to heat and humidity including the impact of workload and clothing.  Heat illness can be defined as “a variety of medical disorders due to environmental, metabolic (physical activity), and workplace exposures to heat.  Heat illness occurs when there is an increase in the worker's core body temperature above healthy levels”.  The common heat illnesses include heat rash, heat cramps, heat exhaustion, heat syncope (fainting), and heat stroke.  As medical conditions, all heat illnesses have signs and symptoms that are critical to early identification and proper response. Contractors should consider starting or updating company heat stress programs considering the direction most regulations are taking.  In the past, a program could basically address shade, rest, and water to prevent many heat stress concerns.  However, recent studies and research shows that a proper heat stress program should include other related topics and contractors would do well to incorporate these issues in a proactive heat stress program.. Heat Stress Programs Workers need to be aware of Personal Rick Factors that affect how heat impacts them individually.  Typical risk factors include age, obesity, poor diet, alcohol use, prescribed and non-prescribed drugs and medications, fatigue, smoking and tobacco use, and existing medical conditions such as asthma, diabetes, and high blood pressure.  Acclimatization is the process of adapting to a hot environment and/or physical demands of work to reduce the risk of heat-related illness and improve physical work capabilities.  This is important at the start of hot weather months or for new workers.  Federal OSHA reports that 3 of 4 fatalities from heat illness happen during the first week of work.  Many regulations are requiring rest periods throughout the workday depending on the potential impact of worker heat stress.  One complication with implementing rest breaks is balancing the need to stay productive in extreme heat conditions. As with all safety and health hazards, heat stress requires hazard recognition and workplace surveillance to proactively identify and prepare for the workday.  The level of anticipated heat illness hazard is related to the temperature and humidity at the worksite or in the shop. While it appears a program “trigger” of 80 degrees Fahrenheit is common, there are other factors to consider including humidity levels.  Heat Index and Wet Bulb Globe Temperature (WBGT) are mentioned in numerous studies as the two most common ways to determine temperature and humidity and companies will need to be familiar with these measurements.  Training is key to any safety and health program and heat stress is no exception since worker self-awareness and supervisory responsibilities are critical to avoiding heat stress emergencies.

For more information on heat stress, heat illness, and related topics, Federal OSHA has these helpful webpages.

• Heat - Overview: Working in Outdoor and Indoor Heat Environments 
• Occupational Safety and Health Administration (osha.gov) Heat Illness Prevention Campaign
• Occupational Safety and Health Administration (osha.gov) Heat Injury and Illness Prevention in Outdoor and Indoor Work Settings Rulemaking
• Occupational Safety and Health Administration (osha.gov) Heat Injury and Illness Prevention Work Group of the National Advisory Committee on Occupational Safety and Health