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High Heat Procedures Elements of Your Written Program and Effective Work Practices

What is in T8CCR 3395?

T8CCR 3395(e) states the following:

  • (e) High-heat procedures. The employer shall implement high-heat procedures when the temperature equals or exceeds 95 degrees Fahrenheit. These procedures shall include the following to the extent practicable:
    • (1) Ensuring that effective communication by voice, observation, or electronic means is maintained so that employees at the work site can contact a supervisor when necessary. An electronic device, such as a cell phone or text messaging device, may be used for this purpose only if reception in the area is reliable.
    • (2) Observing employees for alertness and signs or symptoms of heat illness. The employer shall ensure effective employee observation/monitoring by implementing one or more of the following:
      • (A) Supervisor or designee observation of 20 or fewer employees, or
      • (B) Mandatory buddy system, or
      • (C) Regular communication with sole employee such as by radio or cellular phone, or
      • (D) Other effective means of observation.
    • (3) Designating one or more employees on each worksite as authorized to call for emergency medical services, and allowing other employees to call for emergency services when no designated employee is available.
    • (4) Reminding employees throughout the work shift to drink plenty of water.
    • (5) Pre-shift meetings before the commencement of work to review the high heat procedures, encourage employees to drink plenty of water, and remind employees of their right to take a cool-down rest when necessary.
    • (6) For employees employed in agriculture, the following shall also apply:
      When temperatures reach 95 degrees or above, the employer shall ensure that the employee takes a minimum ten minute net preventative cool-down rest period every two hours. The preventative cool-down rest period required by this paragraph may be provided concurrently with any other meal or rest period required by Industrial Welfare Commission Order No. 14 if the timing of the preventative cool-down rest period coincides with a required meal or rest period thus resulting in no additional preventative cool-down rest period required in an eight hour workday. If the workday will extend beyond eight hours, then an additional preventative cool-down rest period will be required at the conclusion of the eighth hour of work; and if the workday extends beyond ten hours, then another preventative cool-down rest period will be required at the conclusion of the tenth hour and so on. For purposes of this section, preventative cool-down rest period has the same meaning as "recovery period" in Labor Code Section 226.7(a).
T8CCR 3395 (g)(2) states the following:
  • (2) An employee who has been newly assigned to a high heat area shall be closely observed by a supervisor or designee for the first 14 days of the employee's employment.
T8CCR 3395 (i)(2) states the following:
  • (i) Heat Illness Prevention Plan. The employer's shall establish, implement, and maintain, an effective heat illness prevention plan. The plan shall be in writing in both English and the language understood by the majority of the employees and shall be made available at the worksite to employees and to representatives of the Division upon request. The Heat Illness Prevention Plan may be included as part of the employer's Illness and Injury Prevention Program required by section 3203, and shall, at a minimum, contain:
    • (2) The high heat procedures referred to in subsection (e).

Guidance, Best Practices and Warnings

During periods of high heat, it is crucial that employees be monitored for early signs and symptoms of heat illness. This helps ensure that sick employees receive treatment immediately and progression to serious illness is arrested. If an employee suffers syncope (fainting), disorientation, loss of consciousness, or other symptoms of heat illness while working unobserved, initial medical treatment may be tragically delayed.

Observing and monitoring

Because each work site is unique, employers may use different methods for observing and monitoring employees:
  • Where employees work in small groups of no more than 20 workers, direct observation by a supervisor or designee may be sufficient.
  • Where there are too many employees to allow direct observation, the employer may use the buddy system and pair up employees. With the buddy system, the employer must train the employees to stay in contact, observe each other throughout the day, and immediately report any signs or symptoms of heat illness.
  • For employees who are required to work alone, the employer may communicate with the employee by radio or cell phone where there is adequate coverage. The employee must be contacted regularly and as frequently as practicable throughout the day, since an employee in distress may not be able to summon help on his or her own. Whatever method is used, the employer must be able to ascertain the condition of employees at regular intervals and provide emergency services when an employee reports symptoms of heat illness or is unable to respond.


  • All employees must be trained to recognize the signs and symptoms of heat illness and be allowed to call for emergency medical services when necessary.
  • Specifically assign one or a small number of employees per crew to call for emergency medical services. A designated employee may be either supervisory or non-supervisory.
  • Remind supervisors and employees to review high heat procedures in the pre-shift meetings
  • Determine whether the training is required based on the predicted temperature in the area.
  • Cover topics in pre-shift meetings including:
    • staying hydrated and taking cool-down rests
    • identifying the employees who should call for emergency medical services when needed, and how employees will be observed.
  • For employees working remotely, the employer may conduct pre-shift meetings by cell phone or radio.

Agricultural work sites

The following guidance is for agricultural work sites:
  • When the temperature equals or exceeds 95 degrees, employers must provide one 10-minute "preventative cool-down rest period" every 2 hours. During the first 8 hours of a shift, the cool-down periods may be provided at the same time as the rest periods.
  • If employees work longer than 8 hours, the employer must provide an additional 10-minute cool-down rest period every 2 hours. For example, if the shift extends beyond 8 hours, an additional rest period is required at the end of the 8th hour of work. If the shift extends beyond 10 hours, another is required at the end of the 10th hour.
  • Employers must ensure that employees actually take the cool-down rest periods required under this section.
  • Employers are required to provide additional breaks as soon as the temperature equals or exceeds 95 degrees. For example, even if the temperature does not reach 95 degrees until the last half of an 8-hour shift, the employer must ensure that employees take cool-down rest periods starting at the end of the 8th hour of work.

Best Practices

Because of extreme environmental conditions during high heat employees’ physical and mental condition can change even more rapidly into a serious medical condition. The onset of heat illness may be confused with other problems and may not always be obvious before it becomes life-threatening. Therefore, proper planning and taking extra measures may be required to prevent and/or respond to heat illness during high heat.

Extra measures during high heat include but are not limited to the following:

  • Communicating Through Meetings
    During high heat a designated person(s) should hold short, frequent meetings (before and during work) with the workers to review the company heat illness prevention procedures, the weather forecast, emergency response and other additional safety measures.
  • Being Extra Vigilant
    During high heat it is necessary to be extra vigilant. Your communication system is (see Effective Communication) especially important to get more frequent feedback from your employees and supervisors in the field. Then, based on the environmental conditions present and the condition of your employees you can more quickly make the appropriate adjustments, communicate them, and put the changes into place before problems arise or become serious. In high heat:
    • Have supervisors and employees watch each other more closely for alertness and any signs or symptoms of heat illness by using your mandatory "buddy system".
    • Encourage supervisors and employees to communicate about how they are feeling on a more frequent basis.
    • Account for the whereabouts of employees at more frequent intervals throughout the work shift and at the end of the work shift.
  • Changing Work Severity and Duration
    During high heat it may be critical to make adjustments to work activities, see Work Severity and Duration Adjustments.
  • Additional Water Consumption
    • Encourage employees to drink small quantities of water more frequently (i.e., in addition to the four 8-ounce glasses of water, or a total of one quart per hour) throughout the entire work shift to prevent dehydration
    • During high heat, have extra drinking water for employee consumption and make sure that effective replenishment measures are in place
    • Encourage employees to consult with their doctor on salt and mineral replacement.
    • Encourage workers to also drink water before and after work
  • Drink Only Water
    • Encourage employees to avoid drinking alcohol altogether
    • Encourage employees to choose water over other drinks (e.g., sodas and drinks containing caffeine and sugar) because these other drinks may increase dehydration. Also, if employees choose these other drinks they may drink less water.
  • Shade and Additional Cooling Measures
    • Remember that shade is adequate only when it completely blocks the direct sunlight and allows the body to cool. Shade is not adequate when it does not allow the body to cool. In high heat air temperatures in the shade may still be extremely high and not allow the body to cool. For industries other than agriculture, during high heat, you may need to use other alternative cooling measures in addition to shade, (e.g., allowing employees to spend time in air conditioned places). For alternative cooling measures see Shade and Other Cooling Measures.
    • As required, the shade shall be enough to accommodate all employees taking rest breaks or having a preventative recovery.
    • The shaded area shade shall be located as close as practicable to the areas where employees are working.
    • During meal periods, the amount of shade must be enough to accommodate all employees who remain onsite during their meal period.
  • Additional and/or Longer Rest Breaks and Cool Down Rest Periods
    During high heat it is especially important to permit employees the freedom to interrupt work activities to take rest breaks and allow the body to cool. During high heat you may need to allow employees to take more frequent and longer breaks, and more cool down rest periods (see Preventative Cool Down Rest Periods). Remember to provide areas for employees to take their breaks and cool down rest periods which are:
    • Readily accessible and in close proximity
    • Open to the air and ventilated or cooled, or in shaded areas
    • Near sufficient supplies of drinking water
    Keep records of breaks as a best practice.
  • Changing Meals
    • Encourage employees to eat smaller more frequent meals which reduce the heat the body produces as compared to eating large meals less frequently
    • Encourage employees to choose foods with higher water content such as fruits, vegetables and salads


Remember, even employees who were previously fully acclimatized are at risk for heat illness during high heat. This is because during high heat the body does not have enough time to adjust to a sudden, abnormally high temperature or other extreme conditions.