There are considered 3 types of Inspections.
Level 1 inspections-
Are limited to readily accessible portions of the venting system, and accessible portions of the connected appliances and chimney connections. (Standard)
A level 1 inspection is intended for: Routine or annual evaluations of the venting system
Level 2 inspections-
Is a more detailed and thorough than a Level 1 and is recommended inspection when the conditions of use for the appliance or venting system are changing, or when a Level 1 inspection reveals the need for a more detailed inspection.
A level 2 inspection is intended for: Replacement of an appliance with one of dissimilar type, prior to a flue relining, upon sale or transfer of the property, after an event that was likely to cause damage to the chimney i.e. chimney fire, earthquake, sudden occurrence event.
Level 3 inspections-
The most detailed of all the inspection types and includes inspection of concealed areas. This inspection requires destructive action to the building in order to investigate known or suspected problems. (Rare)
NFPA 211 recommends that all chimneys, fireplaces, and vents be inspected annually. In addition to this requirement, there are other times when chimney and venting systems should be inspected, such as:
1. After operating malfunction, any unusual, or sudden occurrence event, such as a chimney fire, lightning strike or earthquake.
2. Prior to purchasing a home with an existing chimney or vent (Level 2)
3. Whenever changes are made to a chimney or vent system, including replacement of connected appliances.
4. Prior to major system repairs.