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 安(an)全帽(mao)(mao)是用(yong)來保護頭頂(ding)而戴的鋼(gang)制(zhi)或類似原料制(zhi)的淺圓頂(ding)帽(mao)(mao)子，防(fang)止(zhi)沖(chong)(chong)(chong)擊(ji)物傷(shang)害頭部的防(fang)護用(yong)品。由(you)(you)帽(mao)(mao)殼、帽(mao)(mao)襯、下(xia)頰帶(dai)和后箍組(zu)成。帽(mao)(mao)殼呈半球形，堅(jian)固、光(guang)滑并有一定(ding)彈性(xing)，打擊(ji)物的沖(chong)(chong)(chong)擊(ji)和穿(chuan)刺動能主(zhu)要由(you)(you)帽(mao)(mao)殼承受。帽(mao)(mao)殼和帽(mao)(mao)襯之(zhi)間留有一定(ding)空(kong)間，可緩沖(chong)(chong)(chong)、分散瞬時沖(chong)(chong)(chong)擊(ji)力，從(cong)而避免或減輕(qing)對(dui)頭部的直(zhi)接傷(shang)害。沖(chong)(chong)(chong)擊(ji)吸性(xing)性(xing)能、耐穿(chuan)刺性(xing)能、側向(xiang)剛性(xing)、電絕緣性(xing)、阻燃性(xing)是對(dui)安(an)全帽(mao)(mao)的基本(ben)技術性(xing)能的要求。