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Heat Disorders

Heat disorders are caused by prolonged exposure to hot temperatures or excessive physical activity, restricted fluid intake, or failure of the body's ability to regulate its temperature. The general term used for heat disorders is hyperthermia.

Heat becomes a problem when humidity, air temperature, and radiant heat combine with hard work to raise body temperature beyond safe limits. Sweat is your main defense. Everyone on the fireline must understand the importance of drinking water often.

There are several terms and types of heat related illnesses which can include heat cramps, heat exhaustion and heat stroke:

Heat cramps are the least serious form of hyperthermia. They are the first sign that the body is having difficulty with increased temperature. Heat cramps are a warning sign that more serious problems may soon develop.

  • Painful muscle spasm, often in the abdomen, back as well as extremities
  • Fatigue
  • Thirst 

Heat exhaustion is more serious than heat cramps. Heat exhaustion results when the body produces more heat than it can dissipate. Inadequate fluid intake can be a major contributing factor. The body may become dehydrated, or its temperature regulation system may begin to fail. 

  • Weakness
  • Extreme fatigue
  • Nausea
  • Headaches
  • Wet, clammy skin
  • Dark yellow or orange urine

Prompt treatment of heat cramps and heat exhaustion is usually successful. Patients recover in a matter of hours or, at most, a day, or two. Heat Stroke poses more serious problems.

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Heat Exhaustion and Heat Stroke symptoms

Heat stroke is a medical emergency. Heat stroke is caused by failure of the body’s heat controls.  Whereas heat cramps and heat exhaustion may be treated locally, heat stroke patients should be medevac’d off the line immediately, by air if possible, as their condition may worsen suddenly.

The main characteristic is altered mental status or confusion.

  • Mental confusion
  • Loss of consciousness
  • Seizures
  • Elevated body temperature (sometimes higher than 105.8) 

The presence or absence of sweating is NOT a criterion for heat stroke.  50% of Heat Stroke victims are still sweating.

Brain damage and death may result if treatment is delayed.

The first steps in treating any form of hyperthermia include:

  • Place in cool shaded environment
  • Remove excess clothing and equipment
  • Cool with fanning and/or water dousing
  • Rehydrate orally with cool water only if conscious and can follow directions
    • Provide liquids which contain electrolytes, i.e. Gatorade, etc.
  • Transport to an emergency facility if recovery is not prompt.
  • Individual is not to go back to work that day.
  • If symptoms persist following 10-15 minutes of treatment, suspect heat stroke, and begin more aggressive cooling therapy and immediate transport to an emergency facility.

You can prevent the serious consequences of heat disorders by improving your level of fitness and becoming acclimated to the heat. Maintaining a high level of aerobic fitness is one of the best ways to protect against heat stress. The fit worker has a well-developed circulatory system and increased blood volume. Both are important to regulate body temperature. Fit workers start to sweat sooner, so they work with a lower heart rate and body temperature. They adjust to the heat twice as fast as the unfit worker.

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NWCG Latest Announcements

ETC/RMC Safety Bulletin: 25-001 New Guidance on Laundering Wildland Fire Clothing to Reduce Contamination

Date: Aug 8, 2025
Questions? Please contact:
Equipment Technology Committee
 Risk Management Committee

The Equipment Technology Committee (ETC) and the Risk Management Committee (RMC) have issued Safety Bulletin 25-001: Laundering to Decontaminate Wildland Fire Clothing. Recent research revealed that wildland fire flame-resistant pants and shirts can be contaminated with chemicals from combustion byproducts, including carcinogens, and that common laundering practices can effectively remove these harmful contaminants from wildland firefighter clothing more effectively than previously understood. It is recommended to decontaminate wildland fire clothing as frequently as possible. 

Frequently Asked Questions about this new information and how to implement recommendations can be found on the NWCG Alerts page. Read the complete ETC/RMC Safety Bulletin: 25-001 to learn more. 

References:

NWCG Alerts

ETC Safety Bulletin: 25-001

Frequently Asked Questions (FAQ) on Laundering to Decontaminate Wildland Fire Clothing

Equipment Technology Committee

Risk Management Committee

FAQ Now Available for Archiving Type 1 and Type 2 Incident Positions

Date: Aug 6, 2025
Questions? Please contact:
Incident and Position Standards Committee

To support the transition to Complex Incident Management (CIM), NWCG will archive all Type 1 and Type 2 Command and General Staff (C&G) position qualifications in January 2026, as outlined in NWCG Executive Board Memo 25-002. To assist with this transition, a new Frequently Asked Questions (FAQ) document is now available.

This resource answers common questions about the status of Type 1 and Type 2 qualifications, impacts to incident qualification management, training requirements, and resource ordering considerations. Review the full FAQ to learn more.

For additional information on CIM and the transition of C&G positions, see NWCG Executive Board Memos 23-005, 24-005, and 25-002, as well as the Incident Workforce and Development Group webpage.

References:

NWCG Type 1 & Type 2 Position Archiving FAQ

NWCG Executive Board Correspondence

Incident Workforce Development Group

Incident and Position Standards Committee

Incident Position Standards and the Next Generation Position Task Books Now Available for UASD, UASM, UASL and UASP

Date: July 31, 2025
Questions?  Please contact:
Interagency Fire Unmanned Aircraft Systems Subcommittee
 

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Books are now available for all four Unmanned Aircraft Systems positions:

  • Unmanned Aircraft Systems, Data Specialist (UASD)
  • Unmanned Aircraft Systems, Manager (UASM)
  • Unmanned Aircraft Systems, Module Leader (UASL)
  • Unmanned Aircraft Systems Pilot (UASP)

The Performance Support Packages for these positions were developed as part of the Incident Performance and Training Modernization effort. These resources support trainees, qualified personnel, and evaluators in their respective roles.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1, scheduled for January 2026.

References:

NWCG Unmanned Aircraft Systems, Data Specialist Position Page

NWCG Unmanned Aircraft Systems, Manager Position Page

NWCG Unmanned Aircraft Systems, Module Leader Position Page

NWCG Unmanned Aircraft Systems Pilot Position Page

Incident Position Standards and the Next Generation Position Task Books Now Available for RADO and INCM

Date: July 30, 2025
Questions?  Please contact:
Incident Logistics Subcommittee
 

NWCG is excited to announce that Incident Position Standards and the Next Generation Position Task Books are now available for Radio Operator (RADO) and Incident Communications Center Manager (INCM).

The Performance Support Packages for these positions were developed as part of the Incident Performance and Training Modernization effort. These resources support trainees, qualified personnel, and evaluators in their respective roles.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1, scheduled for January 2026.

References:

NWCG Radio Operator Position Page

NWCG Incident Communications Center Manager Position Page