When Do You Replace a Carbon Monoxide Detector?

Co Detector

How long does a Carbon Monoxide Alarm last?

Carbon Monoxide (CO) detector alarms have a lifespan of 5-10 years before they lose a sense of smell and cannot detect the deadly gas accurately.

Alarms actual life span can be shorter due to environmental conditions like temperatures and humidity. Worse, carbon monoxide alarms do not detect the presence of carbon monoxide when in end-of-life mode even with a battery change.

A Carbon Monoxide close call for a Twin Cities man is a reminder to check for expired carbon monoxide detectors

Carbon monoxide alarm FAQ.

Where to check for CO detector expiration date?

In 2009, Underwriters Laboratories (UL), began requiring an end-of-life warning to alert homeowners when their carbon monoxide alarm has reached the end of its useful life. Carbon monoxide alarms do not detect the presence of carbon monoxide when in end-of-life mode.

  1. Check the back of your detector for either a build date or an expiration date.
  2. If there’s no date or your CO monitor it is more than seven years old, replace it now.

Where to install carbon monoxide detector alarms?

Illinois homeowners and landlords are required by law Public Act 094-0741 to install at least one approved carbon monoxide alarm, in operating condition, within 15 feet of every sleeping room. 

  1. Carbon monoxide neither rises toward the ceiling nor sinks to the floor.
  2. CO is about the same weight as air. So detectors that don’t have a digital display to read can be mounted anywhere as long as they’re at least 15 in. below ceilings.
  3. Install one on each level of your home, including basement.
  4. Locate CO detector in hallways near bedrooms but at least 15 ft. away from fuel-burning appliances.
  5. Small children around? Consider buying a talking CO detector. A voice warning is more effective at directing children than a shocking horn.
  6. Building owners responsibility is to supply and install all required alarms.
  7. Tenant responsibility is to test and to provide general maintenance for the alarms.

What is carbon monoxide gas? 

Carbon monoxide (CO) is a poisonous, colorless, odorless and tasteless gas. Exposure to a small amount of carbon monoxide CO which is a colorless, odorless gas over time can cause symptoms like shortness of breath, nausea, dizziness, lightheadedness, or headaches. High levels can prove fatal, with approximately 450 people dying every year of CO poisoning, according to the Centers for Disease Control and Prevention.

What is a dangerous level of CO?

As CO levels increase and remain above 70 ppm, symptoms may become more noticeable (headache, fatigue, nausea). As CO levels increase above 150 to 200 ppm, disorientation, unconsciousness, and death are possible.


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