NFPA 121 Standard on Fire Protection for Self-Propelled and Mobile Surface Mining Equipment, 2001 ed. ftp://host229-135-static.15-188-b.business.telecom italia.it/array1/Studio261/009_Blocchi/BASI/1C05_F ONTI_NORME/NFPA/121-2001.pdf, (Std: Fr Prac for Self-Propelled and Mobile Surface Mining Equip - Amer) {253 NFC}