A low-pressure mercury vapordischargelamp is operable in a first mode of operation ('normal mode') and a second mode of operation ('emergency operation').
低压汞汽放电灯操作在第一操作模式（“正常模式”）和第二操作模式（“紧 急操作”）下。
2
Electric dischargelamp or vapor lamp: lighting device consisting of a transparent container within which a gas is energized by an applied voltage and made to glow.
放电灯，亦称蒸气灯，一种照明器件，由一透明外壳构成，其中的气体被外加电压激发而发光。
3
Electric dischargelamp, or vapor lamp: Lighting device consisting of a transparent container within which a gas is energized by an applied voltage and made to glow.