The efficiency of any automatic safety device should be checked before every nitration. 每种自动安全装置应在每次硝化前进行检验。
Yolk is a design for a head protection device which revolutionizes the image and associations the specific user group has with safety equipment. 蛋黄是为头部保护装置所作的设计，它使特定用户群对安全装置的印象及联想发生了革命性的改变。
