US Department of Agriculture, USDA Forest Service, Technology and Development Program Banner with Logos.
Images from various aspects of the T&D Program.
HomeAbout T&DT&D PubsT&D NewsProgram AreasHelpContact Us
  T&D > T&D Pubs > Design Changes for Firefighter Pants T&D Publications Header

Fire Tech Tip
August 2009
5100 Fire
Print this pub
Design Changes for Firefighter Pants

Tony Petrilli, Project Leader

The Forest Service, U.S. Department of Agriculture, first specified flame-resistant (FR) pants for fire personnel in 1974. That year, the Missoula Equipment Development Center announced the availability of Nomex flame-resistant pants for wildland firefighters. Since then, the pants material and design have been changed periodically, mostly in response to feedback from firefighters.


  • Nearly 2,000 firefighters responded to the Missoula Technology and Development Center's 2005 nationwide product review of flame-resistant pants worn by firefighters.

  • The pants design was improved based on the firefighters' responses.

  • The General Services Administration now includes flame-resistant pants made from a para-aramid blend (Kevlar) fabric as well as the existing meta-aramid blend (Nomex) fabric.

2005 MTDC Product Review Leads to Design Changes

In the summer of 2005, the Missoula Technology and Development Center (MTDC) conducted a nationwide product review to evaluate firefighter satisfaction with the current design of FR pants (figure 1). Nearly 2,000 firefighters from various Federal agencies throughout the United States responded. In response to this feedback from firefighters, several design changes were made: stronger seam construction, increased seat/leg room, expanded cargo pockets, different waist adjustment buckles, and new cuff cinch straps. Pants incorporating these changes began to be produced in 2008. The 34-inch inseam length for regular-size pants was changed to 33 inches. A long size with a 36-inch inseam was added. Three inseam sizes (short—30-inch, regular—33-inch, and long—36-inch) will help firefighters find pants that fit better. Existing stocking levels will dictate when pants with all these changes will be available through the General Services Administration (GSA) Wildland Fire Equipment Catalog.

Example of the survey the Missoula Technology and Development Center sent out for firefighters to evaluate flame-resistant pants.
Figure 1—In 2005, MTDC provided forms to firefighters
across the country so they could provide feedback about
flame-resistant pants.

2005 and 2006 Field Trials for New Fabrics

In 2005, MTDC also began evaluating alternative fabrics for use in FR pants. Five new fabrics were chosen for wear testing. The current fabric was included as the experimental control. The six wear test fabrics were:

  1. Current fabric, Nomex (meta-aramid) blend, (Forest Service Specification 5100-88 Type I) 7.5 oz/sq. yd, twill weave, wicking finish

  2. Kevlar (para-aramid) blend, 7.0 oz/sq. yd, ripstop weave, durable water-repellent (DWR) finish

  3. Nomex (meta-aramid) blend, ripstop weave, wicking finish

  4. Nomex (meta-aramid) blend, ripstop weave, durable water-repellent finish

  5. Nomex (meta-aramid) blend, smooth ripstop weave, wicking finish

  6. Indura FR cotton blend, 11 oz/sq. yd, plain weave

The 2005 product review identified two improvements firefighters wanted in FR pants: better protection from certain types of vegetation, such as brush and briars, and better thermal comfort in hot weather conditions, reducing the likelihood of heat stress.

Evaluators thought the FR cotton pants provided the most protection from brush and briars. However, two characteristics led to FR cotton fabric being eliminated from further consideration. The FR cotton readily absorbed water and took a long time to dry. Evaluators also thought the fabric was too hot.

The Kevlar (para-aramid) blend received the second highest rating for protection from brush and briars. This blend had the second "coolest" rating of any fabric tested; only the current fabric was rated cooler. These factors make this fabric the best candidate for offering firefighters increased protection from brush and briars. This fabric also:

  • Was more comfortable in cooler weather
  • Had higher heat protection ratings during thermal and radiant tests
  • Was requested by many firefighters

Forest Service specification (5100-92) for FR pants has been revised to include the para-aramid blend fabric. The 5100-92 specification now includes Type I pants, made with the meta-aramid blend (Nomex) fabric, and Type II pants, made with the para-aramid blend (Kevlar) fabric.

New Firefighter Pants Available Now

The 2009 GSA catalog includes the current meta-aramid blend (Type I, $75.54) pants and a brief announcement of the new para-aramid blend (Type II, $119.89). Both types incorporate the new design features described earlier (figure 2). Initially, the Type II pants will be available only in the most used sizes. Other sizes will be available later. The two choices of fabrics provide firefighters with greater flexibility to match their clothing to the diverse environments where firefighters may work, given their national mobility and extended fire seasons.

Photo of the new firefighter pants.
Figure 2—Type II flame-resistant pants made of a para-aramid
blend in a rip-stop weave are now available through the General
Services Administration.

Forest Service funds can be used to purchase these pants only when they are ordered from the GSA "Wildland Fire Equipment Catalog" or the Wildland Fire Equipment section of GSA Global Supply ( The specific NSN (National Stock Number) ordering number (table 1) must be provided when ordering the pants. For more information on ordering the Type II pants, go to the GSA Fire Program Web page (

Table 1—Type II (para-aramid blend) pants available through the GSA. The inseam lengths are: short (30-inch) and regular (33-inch). Other sizes will be available later.
GSA NSN ordering number Waist size
Inseam length
8415-01-559-3540 28–32 Regular
8415-01-559-3545 28–32 Short
8415-01-559-3543 30–34 Regular
8415-01-559-3542 30–34 Short
8415-01-559-3544 32–36 Regular
8415-01-559-3549 32–36 Short
8415-01-559-3547 34–38 Regular
8415-01-559-3541 34–38 Short
8415-01-559-3548 36–40 Regular
8415-01-559-3546 36–40 Short
The Future

Firefighters are participating in field trials to evaluate lighter weight fabrics in new material blends as a possible replacement for the Type I pants material. The goals are increased thermal comfort in hot weather, improved durability, lower costs and overall firefighter satisfaction.

About the Author

Tony Petrilli is an equipment specialist for the fire and aviation and safety and health programs at MTDC. He has a bachelor’s degree in education from Western Montana College. Tony began working for the Forest Service in 1982 and joined MTDC full time in 2000. He has worked as a firefighter for the Lewis and Clark and Beaverhead National Forests and as a smokejumper for the Northern Region. He is a division/group supervisor, type III incident commander, and has served on more than 20 fire entrapment review or investigation teams.

Additional single copies of this document may be ordered from:

USDA Forest Service
Missoula Technology and Development Center
5785 Hwy. 10 West
Missoula, MT 59808–9361
Phone: 406–329–3978
Fax: 406–329–3719

Electronic copies of MTDC's documents are available on the Internet at:

For additional technical information about firefighter pants, contact Tony Petrilli at MTDC:

Phone: 406–329–3965
Fax: 406–329–3719

Forest Service and Bureau of Land Management employees can search a more complete collection of MTDC's documents, CDs, DVDs, and videos on their internal computer networks at: