Yes, they are as reliable as standalone smoke and carbon monoxide detectors. Inside, there are two sensors, one for smoke and one for carbon monoxide.
a dual sensor smoke and carbon monoxide detector combine electrochemical sensor and photoelectric technology to detect both CO leak and smoldering fires, offering you the best protection and saving you the hassle of installing two separate detectors.
such as this dual sensor smoke and carbon monoxide detector (SR-821THS) from sumring is the ultimate smoke alarm for your home. Re-designed from the inside out, it has an industrial-grade smoke sensor and CO sensor, Its super-efficient sensor detects both fast and slow burning fires and prevent CO poisoning.
– here are the features of the dual sensor smoke and carbon monoxide detector (SR-821THS) :
• 2 in 1 CO & smoke combo detector, built in high accurate electrochemical sensor & infrared photoelectric sensor.
• LCD displays CO concentration: 000~999PPM, and the blue backlight will be activated when alarming.
• If CO gas concentrations over 100PPM or smoke concentration over 0.1%db/m, the buzzer will make sound “di” and the LED light will flash to alert you.
• Alarm Pause(Hush Mode): you can press the test button to stop the alarming sound when non-emergency.
• Test/Reset button to test the unit electronics, check alarm concentration or reset the unit.
• Low Battery Warning: the red LED light and LCD display will remind you when power shortage.
• Powered by 3 * 1.5V AA batteries, ultra-long standby time and low current consumption.
• Suitable for all the places, such as your kitchen, bedroom, bathroom, garage, etc.
why not try “dual sensor smoke and carbon monoxide detector” ？