The weight of the helmet, including the following components: shell; energy-absorbing system; retention system; fluorescent and retroflective trim; ear covers; and a faceshield, goggles, or both. NFPA 1971, 2000 ed
National Fire Protection Association, Illustrated Dictionary of Fire Service Terms, Jones & Bartlett Publishers, MA. USA 2006. https://books.google.com.kw/books?id=W0WIRa3Gl4QC& printsec=frontcover&source=gbs_ge_summary_r&cad=0# v=onepage&q&f=false, (Fr Srvc - Amer) {141}