Carbon monoxide detectors should be replaced after how many years from the date of manufacture?

• A. Seven years
• B. Ten years
• C. Five years
• D. Twelve years

Answer: (A)

Carbon monoxide detectors have a limited lifespan because the sensing element degrades over time, which can reduce their accuracy and reliability. Because this life starts from the date of manufacture, following a defined replacement interval helps ensure you’re protected.

Seven years is the commonly used replacement interval for CO detectors. Many devices are designed to last about seven years, and some models even include an end-of-life indication around that age. Replacing at seven years helps maintain dependable detection rather than risking undetected CO buildup. While some units may be rated five or ten years, seven years is the standard most instructors and safety programs teach as the typical best practice. Always follow the manufacturer’s instructions for your specific model, and replace if an end-of-life indicator appears.