A: The National Fire Protection Association Standard 211 says; “Chimneys, fireplaces, and vents shall be inspected at least once a year for soundness, freedom from deposits, and correct clearances.” It is important to have cleaning and maintenance done when necessary, because even if you don’t use your chimney often, animals may build nests in the flue or you may have other types of deterioration that could make the chimney unsafe to use.