Skip to main content

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.

Return to Top

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.

Return to Top

Print PDF

NWCG Latest Announcements

Updated NWCG Standards for Airtanker Base Operations, PMS 508

Date: March 31, 2025
Questions?  Please contact:
Airtanker Base Operations Unit

The updated NWCG Standards for Airtanker Base Operations (SABO), PMS 508 standardizes operations and procedures at interagency airtanker bases to ensure safe, efficient, and effective operations in support of interagency goals and objectives.

References:

NWCG Standards for Airtanker Base Operations, PMS 508

WFSTAR 2025 Core Component Module Package and 2024 Fire Year in Review Now Available

Date: March 14, 2025
Questions?  Please contact:
Joe Schindel at mschindel@blm.gov
 

The 2025 Core Component Module Package for RT-130, Wildland Fire Safety Training Annual Refresher (WFSTAR) and the 2024 Fire Year in Review are now available on the NWCG website. The 2025 Core Component Module Package provides all content needed to deliver RT-130.

References:

2025 Core Component Module Package

2024 Fire Year in Review Module

NEW! NWCG Wildland Urban Interface Mitigation Field Guide, PMS 053

Date: March 12, 2025
Contact: Wildland Urban Interface Mitigation Committee

The NWCG Wildland Urban Interface Mitigation Field Guide, PMS 053 provides mitigation practitioners at all experience levels with recommendations on the most effective and efficient ways to accomplish mitigation work in communities at risk to wildfire damage or destruction. The content in this guide was written in coordination with the NWCG Standards for Mitigation in the Wildland Urban Interface, PMS 052.

References:

NWCG Wildland Urban Interface Mitigation Field Guide, PMS 053 

Updated, NWCG Standards for Wildland Fire Module Operations, PMS 430

Date: March 11, 2025
Contact: Fire Use Subcommittee
Wildland Fire Module Unit

The NWCG Standards for Wildland Fire Module Operations, PMS 430 standardizes procedures and expectations for Wildland Fire Modules (WFMs). These standards are to be used by staff, supervisors, specialists, and technicians for planning, administering, and conducting WFM operations. These standards will also be used as a measure of WFM qualifications, capabilities, and expected performance, for both Type 1 and Type 2 WFMs.

References:

NWCG Standards for Wildland Fire Module Operations, PMS 430