... method Concentration unit:ppm,%VOL,%LEL,mg/m3 Acousto-optic alarm means:, vibration Working temperature: - 40 ~ 70 ... interface, Lower gas species, right now display vibration motor and buzzer, indicator. All alarm 1 times says ... stopped working, but Is the wording of "screen Alarm" are flashing, if it's electricity shortage, Power ... frame (display with CO, for example) ozone gas alarm (GD80-O3)