1. The Safe-T-Alert™ carbon monoxide alarms are listed to UL 2034 rev. October 1, 1998 residential conditioned and unconditioned area use. They use a semiconductor sensor that is very selective to CO; consequently other gases do not affect them.
2. The two-stage alarm will activate the LOW LEVEL alarm when the alarm is constantly exposed to 60 to 70 ppm of CO for 90 minutes. This alerts you that there is a CO problem well before it becomes dangerous, and meets the UL requirement for an alarm at 70 ppm.For protection from HIGH CO levels the High Level Alarm will activate at 100 ppm.
3. During the mute cycle the LED will continue to signal the presence of CO until the CO has cleared.If the CO level has not dropped below dangerous concentrations within 6 minutes the alarm will resound. When the CO has cleared the alarm returns to normal operation.
4. The 60 series alarms have a memory feature that retains the highest level of CO it detected during an alarm. The memory can be activated with a touch of the test/reset switch. A simple series of flashes and beeps will indicate; 1) Under 100 ppm, 2) under 200 ppm and 3) over 200 ppm detected.