How often should residences test their ground fault circuit interrupters (GFCIs)?

Testing ground fault circuit interrupters (GFCIs) once a month is recommended as a best practice for ensuring safety and functionality. GFCIs are designed to protect against electrical shock by tripping the circuit when a ground fault is detected. Regular monthly testing helps identify any malfunctions or wear that may affect their performance, allowing for prompt repairs or replacements. This frequency ensures that GFCIs are functioning correctly so that they can provide the necessary protection when needed. Relying on less frequent testing could increase the risk of electrical hazards, as a non-functional GFCI might not provide the intended safety measures.