Evaluating Your Work Site for Heat Stress Hazards
Heat stress is a hot topic for OSHA. We've all heard of the agency's campaign to prevent heat stress in outdoor workers, which emphasizes "Water, Rest, Shade."
But except for a provision in the Hazardous Waste Operations and Emergency Response (HAZWOPER) standard, federal OSHA does not have regulations that specifically address heat stress.
The National Institute for Occupational Safety and Health (NIOSH) recently renewed its recommendation for an occupational exposure to hot environments standard after reviewing a large amount of new scientific information on how working in the heat affects workers. NIOSH says "occupational exposure to heat can result in injuries, disease, death, and reduced productivity."
However, even without a specific occupational exposure to heat standard, OSHA can and does cite employers for exposing workers to dangerous and/or Excessive Heat conditions.
The main standard OSHA uses is the General Duty Clause,
Section 5(a)(1) of the Occupational Safety and Health Act, which requires employers to provide a workplace that is "free from recognizable hazards that are causing or are likely to cause death or serious harm to employees."
OSHA will cite the standard for both indoor and outdoor heat hazards.
The courts have interpreted OSHA's General Duty Clause to mean that an employer has a legal obligation to provide a workplace free of conditions or activities that either the employer or industry recognizes as hazardous and that cause, or are likely to cause, death or serious physical harm to employees when there is a feasible method to abate the hazard. This includes heat-related hazards that are likely to cause death or serious bodily harm.
Evaluating Your Work Site for Heat Stress Hazards
When evaluating your work site, OSHA will consult the American Conference of Governmental Industrial Hygienists' threshold limit values (TLV) or other industry consensus exposure limits for heat stress. Inspectors will also ask to see the establishment’s injury and illness logs and conduct employer and employee interviews to determine what action, if any, the employer has taken to prevent heat stress problems.
The compliance officer will conduct a walk-around inspection, checking whether engineering controls are in place and working properly, verifying information obtained from interviews, and performing temperature measurements to identify potential sources of heat stress. The inspector will also note whether employees have access to cool drinking water and shaded rest areas.
Related Standards While OSHA will use the General Duty Clause to protect employees from the heat, the agency also will cite employers for violations of related standards. Five other standards OSHA may cite include:
The Personal Protective Equipment standard (29 CFR 1910.132(d) and 1926.28). Under this standard, employers must evaluate conditions in the workplace and determine the appropriate PPE to protect employees from the hazards identified in the work environment. PPE must not create an additional hazard.
The Sanitation standard (29 CFR 1910.141 and 1926.51). This standard requires employers to provide potable water to employees.
The Medical Services and First Aid standards (29 CFR 1910.151 and 1926.50. In the absence of medical facilities within close proximity, employers must have persons on site who are trained to render first aid.
The Safety Training and Education standard (29 CFR 1926.21). This standard, which applies to the construction industry, requires employers to instruct each employee to recognize and avoid unsafe conditions, understand the regulations that apply to the work site, and to control or eliminate hazards or other exposures to illness and injury.
The Injury and Illness Recordkeeping and Reporting standard (29 CFR 1904). Work-related injuries and illnesses that result in medical treatment (such as intravenous fluids) or the loss of consciousness must be recorded on the employer’s 300 Log. This includes heat-related illnesses.
HAZWOPER Before examining those related standards in detail, it's worth a quick look at the heat-related provisions in the HAZWOPER standard. HAZWOPER applies to employees who are exposed or potentially exposed to hazardous substances, including hazardous waste, and who are engaged in one of the operations described in 29 CFR 1910.120(a)(1)(i-v) and 1926.65(a)(1)(i-v).
One of the potential hazards during a hazardous waste cleanup operation is exposure to heat, especially during the hot summer months. OSHA's 29 CFR 1910.120(g) calls on employers to establish a written PPE program addressing site-specific hazards. The program must take the following into consideration regarding PPE:
Selection
- Use and limitations
- Work mission duration
- Maintenance and storage
- Decontamination and disposal
- Training and proper fitting
- Donning and doffing procedures
- Inspection procedures before, during, and after use
- Evaluation of the effectiveness of the PPE program
- Limitations during temperature extremes, heat stress, and other appropriate medical considerations
PPE Beyond the HAZWOPER regulations, all employers need to consider the possibility that their PPE will contribute to heat stress. OSHA has provided some guidance on the issue in details.
Where might I be exposed to heat stress?
Any process or job site that is likely to raise the workers deep core temperature (often listed as higher than 100.4 degrees F (38°C)) raises the risk of heat stress. Operations involving high air temperatures, radiant heat sources, high humidity, direct physical contact with hot objects, or strenuous physical activities have a high potential for inducing heat stress in employees. Outdoor operations conducted in hot weather, such as construction, warehousing, especially those that require workers to wear semi-permeable or impermeable protective clothing, are also likely to cause heat stress among exposed workers.
Are there additional causal factors for heat stress?
Age, weight, degree of physical fitness, degree of acclimatization, metabolism, dehydration, use of alcohol or drugs, and a variety of medical conditions such as hypertension all affect a person's sensitivity to heat. However, even the type of clothing worn must be considered. Prior heat injury predisposes an individual to additional injury. Individual susceptibility varies. In addition, environmental factors include more than the ambient air temperature. Radiant heat, air movement, conduction, and relative humidity all affect an individual's response to heat.
Drinking Water
OSHA's Sanitation standard requires employers to provide fresh drinking water to employees in visible locations that are close to work sites. This is especially important where employees are working in hot environments. The regulations mandate potable water for drinking, washing hands, and preparing food. The agency defines potable water as water that meets the standards for drinking purposes of state or local authorities or that meets EPA standards.
Drinking water dispensers must be capable of closing and must be equipped with a tap. Open containers for dipping are not allowed, and neither are common cups. To prevent occupational heat stress, OSHA says drinking water should have a palatable (pleasant and odor-free) taste and the water temperature should be 50° F to 60° F, if possible.
First Aid OSHA's Medical and First Aid standard says that in the absence of a nearby hospital, there needs to be someone trained to render first aid, and first aid supplies must be readily available. Generally, OSHA interprets "readily available" to mean a response time of 3-4 minutes.
Employers should consider the most likely types of injuries for the site when assembling first aid supplies. In hot working conditions, this would include supplies to treat heat-related illnesses (e.g., cold packs). Train employees to recognize the signs of heat stress in themselves and their co-workers and know how to offer first aid. You must also provide a way to promptly transport an injured person to a physician or hospital if necessary.
Injury and Illness Recordkeeping and Reporting OSHA's Injury and Illness Recordkeeping and Reporting standard at Part 1904 requires employers to maintain a log of work-related injuries and illnesses (the OSHA 300 Log). Injuries and illnesses that are recordable on the log are new, work-related, and meet one or more of the following criteria: death, days away from work, restricted work, job transfer, loss of consciousness, or medical treatment beyond first aid.
Examples of medical treatment are prescription medications and intravenous fluids. Medical treatment does not include diagnostic procedures, visits to the emergency room, or fluids given by mouth. If an employee needs medical treatment for heat stress, you would mark that as an illness on the log.
In addition, if an employee dies or is hospitalized from work-related heat stress, you must report that to OSHA. Reports must be made directly by calling the nearest OSHA office, OSHA's national number at 800-321-6742, or online at www.osha.gov. Reports of a death must be made within eight hours and hospitalizations within 24 hours.
