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Fuel Moisture Sampling

  1. Online Fuel Moisture Sampling History
  2. Fuel Moisture Sampling Procedures

Online Fuel Moisture Sampling History

Fuel moisture sampling can provide useful insight to current conditions if it is done consistently throughout each fire season. Results from sampling efforts around the United States are stored in the National Fuel Moisture Database. Results for sampling history of both live and dead fuels are available for locations around the United States.

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Fuel Moisture Sampling Procedures

General Guidelines

  • Record site name, date, time, observer name, observed weather, general site description.
  • DO NOT collect samples if water drops or dew are present on samples.
  • Keep samples in a cool and dry location.
  • Seal containers with tape that will not leave residue.

Live Fuel Samples

  • Only collect foliage or needles and very small twigs remove flowers, seeds, nuts, or berries.
  • Pack containers loosely to avoid spillage but ensure container is full.
  • Include stems of herbaceous plants.
  • Replace lid on container immediately after collecting sample.

Dead Fuel Samples

  • Samples should not be attached to live trees or shrubs.
  • Avoid decayed samples that crumble or splinter when rubbed.
  • Collect samples from several different plants.
  • Ensure container is full or about 20 grams.
  • Do not collect buried samples.
  • Pick samples of different size within the time lag class.
  • Recently fallen material should be avoided.
  • Remove all lichen, moss, and very loose bark from sample.

Duff and Soil Samples

  • Remove all soil and live tree or plant roots from sample.
  • Avoid any soil particles in duff samples and vice versa.

Litter Samples

  • Collect only uncompacted dry litter from both sunny and shady areas.

Handling and Measuring Samples

  • Preheat drying oven between 60°C (140°F) – 100°C (212°F). Be sure to note temp used.
  • Place sample cans with closed lids on scale and record wet weights.
  • Remove lid just prior to placing in oven. If material is lost, re-weigh sample
  • Dry sample for 24 hours (very wet samples 48 hours).
  • Replace Lids immediately after sample is removed from oven and weigh
  • Calculate fuel moisture using worksheet provided here:
Image
Fuel moisture sampling and estimation. This table provides means for tracking sample weights and calculating gravimetric fuel moisture.

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NWCG Latest Announcements

NEW! S-290, Intermediate Wildland Fire Behavior (Blended) Available Now

Date: Aug 15, 2025
Questions? Please contact:
Fire Behavior Subcommittee

NWCG is excited to announce that the S-290, Intermediate Wildland Fire Behavior (Blended) training is now available on the Wildland Fire Learning Portal. S-290 (Blended) training combines online training and instructor-led training components that support individuals working towards any Single Resource Boss or Fire Effects Monitor incident qualifications.

This second course in the series collectively serves to develop fire behavior prediction knowledge and skills, and provides more detailed information on fuels, weather, and topography that affect wildland fire behavior for safety purposes.

Students are required to finish the prerequisite S-190, Introduction to Wildland Fire Behavior, before enrolling in S-290, Intermediate Wildland Fire Behavior (Blended).

References:

S-290, Intermediate Wildland Fire Behavior (Blended)

S-190, Introduction to Wildland Fire Behavior

Wildland Fire Learning Portal

NEW! S-271, Helicopter Crewmember (Blended) Now Available

Date: Aug 14, 2025
Questions? Please contact:
Interagency Helicopter Operations Subcommittee

The S-271, Helicopter Crewmember (Blended) is now available. Developed through the Incident Performance and Training Modernization (IPTM) effort, this training supports individuals working towards Helicopter Crewmember (HECM) incident qualifications. 

S-271, Helicopter Crewmember (Blended) training combines online training and instructor-led training components. This course is designed to provide students with the knowledge and skills necessary to perform the duties of the HECM position, as described in the NWCG Incident Position Standards for Helicopter Crewmember, PMS 350-22.

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:

S-271, Helicopter Crewmember (Blended)

NWCG Helicopter Crewmember (HECM) Position Page

Wildland Fire Learning Portal

Incident Position Standards and Next Generation Position Task Books Now Available for FBAN and LTAN

Date: Aug 13, 2025
Questions? Please contact:
Fire Behavior Subcommittee

NWCG is excited to announce that Incident Position Standards and Next Generation Position Task Books are now available for Fire Behavior Analyst (FBAN) and Long Term Fire Analyst (LTAN).

The Performance Support Packages for these positions were developed as part of the Incident Performance and Training Modernization (IPTM) 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 Fire Behavior Analyst Position Page

NWCG Long Term Fire Analyst Page

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