The answer to 'how to test carbon monoxide detector' is to test your carbon monoxide (CO) detector regularly, at least once a month, to ensure it is working properly. To test your CO detector, first make sure it is powered on and not expired or damaged. Then, locate the test button, usually marked with 'Test' or a symbol. Press and hold the test button until the alarm sounds, which indicates the detector is functioning correctly. If the alarm does not sound, the detector may need to be replaced.
It's also important to replace the batteries in your CO detector according to the manufacturer's recommendations, typically every 6 months to 1 year. Additionally, you should have your CO detector professionally inspected and calibrated every 5-7 years to ensure it is accurately detecting CO levels in your home.