Chimney Safety Facts
As previously stated, the National Fire Protection Association recommends that chimneys be inspected yearly and serviced if necessary on a yearly basis. This includes fireplaces, wood stoves, gas, oil, and pellet venting appliances. They have also determined that there shall be three levels of inspection for these services.
Level One
Basic visual inspection of chimney. Should be performed annually. This type of inspection is purely a "visual" inspection. No tools or ladders should be necessary to perform this level of inspection. All subjects of a Level One inspection are as follows: Observation of proper contructions and condition of accessible portions of the chimney structure and all enclosed flues. Proper clearances from combustibles in accessible locations. Size and suitabilty of flues for connected appliances.
Level Two
A Level Two inspection is indicated when further observation is needed during a Level One. All subjects for a Level Two inspection are as follows: All accessible portions of the chimney exterior and interior, including areas within accessible attics, crawl spaces, and basements, and accessible portions of the appliance and chimney connections.
Level Three
Includes all subjects of Level One and Level Two inspections. Shall include removal of componets of the building or chimney. Removal of components shall be required to gain access to areas that require inspection. This type of inspection requires demolition to inspect areas that are unreachable.
For more information on inspections visit the NFPA website.
For reference, here is a diagram of the basic inner-workings of a chimney.