Radiant protective performance · RPP
Tests garment material or a composite at a radiant heat flux of approximately 21 kW/m².
RPP ≥ 7 cal/cm².
NFPA 1977
Historical requirements for wildland and urban-interface firefighting PPE
Requirements & test methods
NFPA 1977:2022 addresses protective clothing and equipment for wildland and urban-interface firefighting. These provisions are now consolidated into NFPA 1950.
Flame resistance
Measures vertical-flame response after the specified conditioning and laundering.
Garment fabrics: char length ≤ 100 mm; afterflame ≤ 2 s; no melting or dripping.
Heat resistance and shrinkage
Tests individual garment layers for 5 min at 260°C.
Shrinkage ≤ 10% in either direction. Checks melting, dripping, separation, ignition and charring.
Heat loss and dimensional stability
Measures garment-composite heat loss and cleaning shrinkage. The THL requirement excludes cold-weather outerwear and winter liners.
Wildland garment requirements in the 2022 edition:
| Property | Requirement |
|---|---|
| Total heat loss · garment composite | ≥ 500 W/m² |
| Cleaning shrinkage | ≤ 5% in either direction |
Strength and certification
Measures tear and seam forces in N and covers garment design and labeling.
NFPA 1977:2022 covers wildland and urban-interface PPE; its consolidated successor is NFPA 1950.
Where the standard is used
Related protective fabrics
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