Audible alarm and LED warning. COD100B has LED status indicators; green for power, amber for fault and red for alarm. Alarm level 85dB @ 1m (COD100B), 85dB @ 3m (SD102P). CO alarm level 33ppm: 120 mins55ppm: within 60 to 90 mins110ppm: within 10 to 40 mins330ppm: within 3 mins.
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