Carbon Monoxide (CO) is a colorless, odorless gas that can accumulate to dangerous levels in homes and other buildings when fuel-burning appliances and engines are operated improperly. When breathed, CO displaces oxygen in the blood, depriving the heart, brain, and other organs of the oxygen they need to function. CO poisoning can cause a range of symptoms including frontal headaches within one to two hours, dizziness and nausea within 45 minutes and unconsciousness or death within three hours.

Using Low-Level CO Detectors Safely: Expert Recommendations

While most standard voc monitors are designed to trigger an alarm only when the concentration reaches 70 parts per million (ppm) or higher, long-term exposure to low concentrations can be equally harmful, especially in households with young children and elderly family members who are more sensitive to this poisonous gas. Low-level CO monitors such as the CO Experts Defender LL 6270 and the CO EXPERTS Home Safety PRO-10 begin warning at much lower concentrations, enabling users to take action immediately.

Ross Trethewey tested eight different models of low-level CO monitors in a controlled environment to test for accuracy and ease of use, measuring their ability to alert at concentrations below the threshold required by the Underwriters Laboratories 2034 standard. All eight models performed well, reporting accurate CO readings and activating the preset alert when set. Some of the models included a digital display that updated every 15 seconds and a peak level memory feature that displayed the highest CO concentration measured since the last reset.