Event Details

Outdoor Ambient Heat Exposure

Public Hearing on Proposed Rules
Wednesday, May 3, 2023
10 a.m.


Clark College at Columbia Tech Center
18700 SE Mill Plain Blvd.
Vancouver WA 98683

A pre-hearing overview will occur at 9:00 a.m., one hour prior to the start of the public hearing. The hearing will start at 10:00 a.m. and continue until all oral comments are received.

L&I encourages the submittal of written comments, due by 5:00 p.m. on May 11, 2023.


The purpose of this rulemaking is to update the outdoor heat exposure rules under chapter 296-62 WAC, General Occupational Health Standards, and chapter 296-307 WAC, Safety Standards for Agriculture. On June 28, 2021, L&I received a petition for rulemaking requesting changes to L&I’s rules to include more specific requirements to prevent heat-related illness and injury. The petition for rulemaking was accepted recognizing the need to reexamine the current rules, especially in light of information suggesting the occurrence of heat illnesses below the current trigger temperatures and the increasing temperatures experienced in our state since the rule was first established in 2008. L&I filed emergency rules related to outdoor ambient heat in the summer of 2021 and 2022 to protect outdoor workers from heat-related illnesses due to outdoor heat exposure. The current rules do not affirmatively address preventative measures to avoid overheating other than access to drinking water. The hazards of heat are well documented and research suggests the occurrence of heat-related illnesses below the current trigger temperatures. Research also documents increased temperatures in Washington since the rule was first established. The adopted updates add the importance of acclimatization and considerations for cool-down rest periods, gradual increase of work in the heat and importance that employees are unable to build tolerance to working in the heat. They also add the importance of taking preventative cool-down rest periods, and mandatory rest periods when temperatures exceed 90 degrees Fahrenheit. They add training requirements for procedures for shade or other means to reduce body temperature, and employer’s procedures for close observation of employees. Finally, they add the importance of considering the use of engineering or administrative controls to reduce exposure.