How often shall household smoke alarm systems be tested according to NFPA 72?

Household smoke alarm systems should be tested monthly according to NFPA 72, which is the National Fire Protection Association's standard for the installation, maintenance, and use of fire alarm systems. Monthly testing is essential to ensure that the smoke alarms are functioning properly and can reliably alert occupants in case of a fire.

This testing frequency is recommended because smoke alarms are critical for safety, and regular testing helps identify any potential malfunctions or issues with the devices, such as dead batteries or faulty sensors. In addition to monthly testing, it's also advisable for homeowners to replace the batteries at least once a year and to replace the smoke alarm units themselves every ten years.

The other options, while they may seem reasonable, do not align with the NFPA 72 guidelines aimed at maintaining optimal safety standards in residential settings. Quarterly and yearly testing would not provide the same level of confidence in the operational status of smoke alarms, potentially putting lives at risk during a fire emergency.