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Preventing and Responding to Heat Illness

Elements of Your Written Program and Effective Work Practices


What is in T8CCR 3395?

T8CCR 3395(d)(3) states the following:

(d) Access to shade.

(3) Employees shall be allowed and encouraged to take a cool-down rest in the shade for a period of no less than five minutes at a time when they feel the need to do so to protect themselves from overheating. Such access to shade shall be permitted at all times.

Except for employers in the agriculture industry, cooling measures other than shade (e.g., use of misting machines) may be used in lieu of shade if the employer can demonstrate that these measures are at least as effective as shade in allowing employees to cool. See Provide Cooling Using Alternative Measures.

Best Practices and Warnings

Men taking a break under a tree - shaded area

Cool down rests help workers to recover from the heat and prevent overheating. A Cool Down Rest Period (CDRP) is not the same as regularly scheduled or other rest breaks (see Benefits of Rest Breaks). Cal/OSHA requires that employees be given a CDRP if they are suffering from heat illness, or believe they need a CDRP. Rest breaks help cool the body to eliminate the need for a CDRP. There are numerous ways to enhance cooling the body during CDRPs and rest breaks (see Sufficient Amounts of Drinking Water and Shade and Other Cooling Measures).

Best Practices

Providing Cool Down Rest Periods

When providing cool down rest periods make sure to:

  • Train your employees and supervisors so they understand the importance of Cool Down Rests in preventing heat illness
  • Train your employees and supervisors on your Emergency Response Procedures
  • Use locations for cool down rests which are:
    • Available to all employees and supervisors at all times
    • Spacious enough to accommodate workers in a relaxed body posture
    • In the shade and are either open to the air or provided with ventilation or cooling
    • Near sufficient supplies of drinking water
  • Have supervisors and /or other designated person(s) closely monitor the employee during Cool Down Rests
  • Ensure that employees recognized as having any of the symptoms of heat illness are never left alone or sent home without medical authorization
  • Ensure employees frequently drink sufficient amounts of water


A cool down rest period is not a substitute for the treatment of heat illness by medical personnel. The progression to serious heat illness can be rapid. The initial symptoms alone might be an indication of a serious heat exposure. Therefore, employees or supervisors should be encouraged never to discount any discomfort or symptoms they have noticed or are experiencing.

If any of the signs and symptoms of heat illness (e.g., headache, muscle cramps, fatigue, fainting, seizures, unusual behavior, nausea or vomiting, hot dry skin, or unusually profuse sweating) are recognized or experienced, they should be reported immediately. Then, worksite first aid procedures should be initiated by a trained and certified first aid provider followed immediately by emergency response procedures as indicated by first aid assessment.


Because of extreme environmental conditions during high heat, the risk of developing heat illness is even greater. Employees’ physical and mental condition can change even more rapidly into a serious medical condition. Therefore, during high heat it is even more important not to discount any discomfort or symptoms of heat illness and to immediately report any of these problems to a supervisor.