437-004-1131 Heat Illness Prevention (1) Scope and application. This standard applies whenever an employee performs work activities, whether in indoor or outdoor environments, where the heat index (apparent temperature) equals or exceeds 80 degrees Fahrenheit. Note: When another applicable standard addresses other hazards that may be present, employers must comply with the requirements of that standard and this standard. Where the requirements of one standard are more protective than another for the same hazard, employers must follow the requirements that provide the higher level of employee protection. (a) The following workplaces and operations are exempt from the requirements of this standard. (A) Incidental heat exposures where an employee is not required to perform work activities for more than 15 minutes in any sixty-minute period. (B) Exposures to heat generated from the work process – such as occurs in bakeries – is not subject to this standard. In such cases, employers must follow the requirements of OAR 437-002-0144(2). (C) All emergency operations that are directly involved in the protection of life or property, or the restoration of essential services, such as evacuation, rescue, medical, structural firefighting, law enforcement, utilities, and communications, when employees are engaged in those operations. (D) Buildings and structures that have a mechanical ventilation system that keeps the heat index below 80 degrees Fahrenheit. (b) The following workplaces and operations are partially exempt from certain requirements of this standard. (A) Employers whose employees perform either “rest” or “light” workloads, as defined in Table 1.1 of Appendix A: Mandatory Information for Heat Illness Prevention, are exempt from the requirements of sections (3) through (10) only when the heat index is less than 90 degrees Fahrenheit. (B) Associated support activities for wildland firefighters, such as fire camp services and fire management, are exempt only from the requirements of section (7). (C) Employees who work from home are subject only to the training requirements in sections (9) and (10). (2) Definitions. (a) Acclimatization - Temporary adaptation of the body to work in the heat that occurs gradually when a person is exposed to it. Acclimatization peaks in most people within seven to fourteen days of regular work for at least two hours per day in the heat. This time frame applies to fit individuals with no underlying medical conditions. (b) Drinking water - Potable water that is suitable to drink and that is cool (66 oF – 77 oF) or cold (35 oF – 65 oF). (c) Heat Illnesses - Medical conditions resulting from the body's inability to cope with a particular heat load, and includes heat cramps, heat exhaustion, heat syncope, and heat stroke. (d) Shade - Blockage of direct sunlight is shade. One indicator that blockage is sufficient is when objects do not cast a shadow in the area of blocked sunlight. Shade is not sufficient when heat in the area of shade defeats the purpose of shade, which is to allow the body to cool. For example, a car sitting in the sun does not provide acceptable shade to a person inside it, unless the car is running with working air conditioning. Shade may be provided by any natural or artificial means that does not expose employees to unsafe or unhealthy conditions, and that does not deter or discourage access or use. (e) Temperature-controlled environment – an indoor setting where the temperature is maintained with a mechanical cooling system. (3) Access to shade. Establish and maintain one or more shade areas that are immediately and readily available to exposed employees that are outdoors when the heat index in the work area equals or exceeds 80 degrees Fahrenheit. The shade areas must meet the following criteria: (a) The shade area must either be open to the outside air (at least three open sides) or provide mechanical ventilation for cooling. (b) The amount of shade present must be at least enough to accommodate the number of employees on recovery or rest period, so that they can sit in a normal posture fully in the shade. Employees must remove any PPE that retains heat, such as chemical resistant suits, during recovery and rest periods. (c) The shade must be located as close as practical to the areas where employees are working. (d) Shade present during meal periods must be large enough to accommodate the number of employees on the meal period that remain onsite. (e) If trees or other vegetation are used to provide shade, such as in orchards or forests, the thickness and shape of the shaded area must provide sufficient shadow to protect employees. Exception: When the employer can demonstrate that providing access to shade is not safe or it interferes with the ability of employers and employees to complete the necessary work in a particular situation, for example, during high winds or when an employee is walking through range land, employers must identify and implement alternative cooling measures that provide equivalent protection such as providing cooling vests (either with fans or ice packs), water-dampened cotton clothing, or similar effective measures. The Heat Illness Prevention Plan under section (8) must include the use, care, and maintenance of the alternative cooling methods, in writing. (4) Drinking water. Ensure that a sufficient supply of drinking water is immediately and readily available to exposed employees at all times, at no cost, when the heat index in the work area equals or exceeds 80 degrees Fahrenheit. (a) Supplied drinking water must be either cool or cold, see subsection (2)(b). (b) Supply each employee with enough drinking water to enable them to consume up to 32 ounces per hour. Employers are not required to supply the entire quantity of drinking water needed for all employees on a full shift at the beginning of the shift. Employers may begin the shift with smaller quantities of drinking water when effective procedures are established to replenish the water consumed during the shift. (c) Employees must have ample opportunity to drink water required under this section. Note: Drinking water packaged as a consumer product and electrolyte-replenishing beverages that do not contain caffeine (for example, sports drinks) are acceptable substitutes, but should not completely replace required water supplies. (5) High-heat practices. When engineering controls (such as fans or air conditioning) and administrative controls (such as scheduling work during the cooler part of the day or limiting an employee’s exposure) do not reduce an employee’s exposure to a heat index of less than 90 degrees Fahrenheit, implement and maintain high-heat practices and procedures by following subsections (5)(a) through (e) below. (a) Communication must occur in a language and vocabulary readily understood by all employees, by voice, electronic, or other equally-effective means, so that employees at the worksite can contact a supervisor at any time, when necessary. An electronic device, such as a cell phone, may be used for this purpose only if reception in the area is constant and reliable. (b) Implement one or more of the following to promptly identify any employee suspected of experiencing heat-related illness: (A) Regular communication with employees working alone, such as by radio, cellular phone, or other alternative means; (B) Create a mandatory buddy system; or (C) Implement other equally-effective means of observation or communication. (c) Designate and equip one or more employees at each worksite as authorized to call for emergency medical services, and allow other employees to call for emergency services when designated employees are not immediately available; such a practice supplements existing requirement to ensure that emergency medical care is immediately available in all workplaces, as required by OAR 437-004-1305(4). (d) When employees work in buildings and structures that do not have a mechanical ventilation system, employers must: (A) Directly measure the temperature and humidity in these places at the same time and location when occupied by employees to determine the current indoor heat index; (B) Use the National Institute for Occupational Safety and Health’s (NIOSH) Heat Safety Tool app to determine the heat index outside of the building or structure and assume that it is the same inside (See section 2 in Appendix A: Mandatory Information for Heat Illness Prevention); or (C) If the structure is designed or otherwise known to be affected by outdoor humidity, for example, hoop houses and greenhouses in nursery operations, the employer must measure and use the actual humidity inside the structure. (e) Develop and implement a written heat illness prevention rest break schedule that protects employees exposed to a heat index equal to or greater than 90 degrees Fahrenheit. Employers must choose and implement only one of the three options; choose either (A), (B), or (C) as described below. Note: The purpose of the heat illness prevention rest breaks is to allow the body to cool down and recover from working when the heat index equals or is greater than 90 degrees Fahrenheit. Note: Option (A) allows an employer to implement a self-designed schedule by building on a minimum rest break schedule using four specified elements. Option (B) allows an employer to implement a schedule by using an example heat illness prevention plan designed by NIOSH. Option (C) allows an employer to implement a schedule by using a simplified schedule designed by Oregon OSHA and based on a high-heat scenario in the NIOSH plan. (A) Employer-designed heat illness prevention rest break schedule: Implement a written employer-specific, heat illness prevention rest break schedule using the minimum rest break durations and intervals in Table 1. Employers must protect employees from heat illness by integrating the elements in subsections (i) through (iv) into to their heat illness prevention rest break schedule, which may increase the duration or interval of the rest break beyond the minimum requirements to be protective. (i) The effect of personal protective equipment (PPE) on the body’s ability to retain heat; (ii) The effect of the type of work clothing on the body’s ability to retain heat; (iii) Relative humidity, whether work activities are indoors or outdoors; and (iv) The intensity of the work being performed. Note: Employers should consider the effect of exposure to direct sunlight when developing employer-specific heat illness prevention rest break schedule. [Table 1. Minimum employer-designed heat illness prevention rest break schedule, upon which subsections (i) through iv) must be applied:] (B) NIOSH work/rest schedule: Implement a written heat illness prevention rest break schedule using the information found in section 3 of Appendix A: Mandatory Information for Heat Illness Prevention based on NIOSH recommendations. Note: The NIOSH work/rest schedule uses unadjusted ambient temperatures (in degrees Fahrenheit), and employers must follow the instructions underneath Table 3.1 in Appendix A: Mandatory Information for Heat Illness Prevention. Employers must be aware that different work/rest schedules exist for those wearing chemical-resistant suits; see Table 3.2 in Appendix A: Mandatory Information for Heat Illness Prevention. (C) Simplified heat illness prevention rest break schedule: Implement a written simplified heat illness prevention rest break schedule using Table 2. [Table 2. Minimum simplified rest break schedule:] Note: The Table 2 heat illness prevention rest break schedule is only required during the specified heat index. (f) The heat illness prevention rest breaks under subsection (5)(e) are only required during the specified heat index, and may be provided concurrently with any other meal or rest period required by policy, rule or law – if the timing of the preventative rest break coincides with the otherwise required meal or rest period. However, the heat illness prevention rest break must be calculated using only the time spent in the shade and when employees are not performing work other than “rest” or “light” work. The requirement for heat illness prevention rest breaks does not prohibit “rest” or “light” work-related activities conducted in a temperature-controlled environment, such as paperwork, at the discretion of the employee. (g) Except when the heat illness prevention rest breaks coincide with the existing unpaid meal break, the heat illness prevention rest break is a work assignment. Heat illness prevention rest breaks are only required during the time of the shift that the heat index equals or exceeds 90 degrees Fahrenheit. (6) Emergency medical plan. The employer’s Emergency Medical Plan must address employee exposure to excessive heat, in accordance with OAR 437-004-1305(4). These plans must address the types medical situations that employees could encounter, including those conditions relating to excessive heat exposure. (7) Acclimatization plan. Develop and implement an acclimatization plan and procedures in writing. Employers must choose between two options, either (a) or (b) as described below, and implement the chosen plan. (a) Employer-designed acclimatization plan option: Employers who develop their own acclimatization plan must integrate and implement the following factors into their program: (A) Acclimated and unacclimated workers; (B) The effects of clothing and personal protective equipment on adding to the heat burden of workers; (C) The personal and environmental risk factors that put workers at a higher risk of heat-related illness; (D) Re-acclimatizing workers as necessary, either due to changes in the weather or a worker spending more than seven days away from the job; and (E) The use and maintenance of auxiliary cooling systems such as water-cooled garments, air-cooled garments, cooling vests, and wetted overgarments. (b) NIOSH acclimatization plan option: Employers that choose not to develop their own acclimatization plan must follow the acclimatization plan developed by the Centers for Disease Control and Prevention and NIOSH; see section 4, Appendix A: Mandatory Information for Heat Illness Prevention. Note: Based upon the variable weather patterns across the state, Oregon OSHA recognizes that there is no “one-size-fits-all” acclimatization plan. Employers should be aware that acclimatization to heat takes longer for unfit individuals compared to fit individuals. Note: Employers should consider the effect of exposure to direct sunlight when developing their acclimatization plan. (8) Heat illness prevention plan. Develop, implement, and maintain an effective heat illness prevention plan in writing. The plan must be made available at the worksite to employees and to Oregon OSHA upon request. The plan must contain at least the following information: (a) How employees will be trained on the hazards of heat exposure and the necessary steps to prevent heat-related illnesses; (b) How to recognize the symptoms of dehydration, and how to respond to suspected heat-related illnesses in others; (c) How sufficient amounts of cool, potable water in work areas will be provided; (d) How employees will be provided frequent opportunities and encouragement to stay hydrated by drinking water; (e) How employees will be provided sufficient space to rest in a shaded area or cool climate-controlled area, and where heat-affected employees may cool off and recover when signs and symptoms of heat-related illnesses are recognized; (f) How the employer will implement the heat illness prevention rest break schedule when necessary to keep employees safe; and (g) How the employer will implement heat acclimatization procedures for new employees or employees returning to work from extended absences of seven or more days. (9) Supervisor and employee training. Provide heat illness prevention training to all employees, including new employees, supervisory and non-supervisory employees in a language and vocabulary readily understood, and in a manner that facilitates employee feedback. Such training must be provided annually before employees begin work that should reasonably be anticipated to expose them to the risk of heat illness, and include at least the following: (a) The environmental and personal risk factors (for example, chronic obstructive pulmonary disease, asthma, kidney disease, obesity, etc.) for heat illness that may limit an individual’s tolerance to excessive heat, as well as the added burden of heat load on the body caused by exertion, clothing (See section 5 in Appendix A: Mandatory Information for Heat Illness Prevention), and personal protective equipment; (b) The employer's procedures for complying with the requirements of this standard, including, but not limited to, the employer's responsibility to provide water, heat index information (including the risks to experiencing a heat-related illness), shade, preventative rest breaks, and access to first aid, as well as how employees can exercise their rights under this standard without fear of retaliation; (c) The importance of frequent consumption of small quantities of water, up to 32 ounces per hour, when the work environment is hot and employees are likely to be sweating more than usual in the performance of their duties; (d) The concept, importance, and methods of the acclimatization plan pursuant to the employer's procedures under section (8); (e) The different types of heat illness, the common signs and symptoms of heat illness, and the appropriate first aid and emergency response to the different types of heat illness, including how heat illness may progress quickly from mild signs and symptoms to a serious and life-threatening condition; (f) The importance for employees to immediately report to the employer, directly or through the employee's supervisor, signs and symptoms of heat illness in themselves or in others; and (g) The effects of nonoccupational factors (drugs, alcohol, obesity, etc.) on tolerance to occupational heat stress. (10) Training documentation. Verify compliance with section (9) by preparing and maintaining written or electronic training records that can be provided to Oregon OSHA upon request. Such records must contain the name or identification of each employee trained, the date(s) of the training, and the name of the person who conducted the training. The most recent annual training record for each affected employee must be maintained. [ED. NOTE: To view attachments referenced in rule text, click here to view rule.] Statutory/Other Authority: ORS 654.025(2), 654.035 & 656.726(4) Statutes/Other Implemented: ORS 654.001 through 654.295 History: OSHA 3-2022, adopt filed 05/09/2022, effective 06/15/2022