... leak leakage concentrations reach concentrations, when the alarm set out, sound-light alarm detector, and the launch of the ... the aging, poisoning, avoid misstatement, omission.· Can independent alarm, also can with the security system, the village intelligence ... temper, etc.Specifications· Detect principle:semiconductor· Detected gasNG· alarm concentration:4%LEL±3%LEL· response time:30S· Power ...