Many homeowners think their chimneys only need to be swept and inspected if they burn wood.  However, almost all heating appliances, be they gas, oil, wood or coal, rely on the chimney to safely vent toxic and corrosive gases out of the house.  The National Fire Protection Association Standard 211 states that - "Chimneys, fireplaces, and vents shall be inspected at least once a year for soundness, freedom from deposits, and correct clearances. Cleaning, maintenance, and repairs shall be done if necessary." 

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