Proximity Protective Trouser : A proximity protective garment; an element of the proximity protective ensemble that is designed to provide minimum protection to the lower torso and legs, excluding the ankles and feet
NFPA 1976 Standard on Protective Ensemble for Proximity Fire Fighting, 2000 ed. https://www.nfpa.org/assets/files/AboutTheCodes/19 76/TIA1976-00-1.pdf, (Std: Prot Ens for Proximity Fr Fight - Amer) {430 NFC}