Class II inspections should be performed every 2 to 5 years. A Class II inspection must be performed during a chimney shut-down and includes the scope of a Class I inspection, plus a full-height interior and exterior inspection.

Additional scope may include:

• Full or partial thickness core samples of concrete or brick
• Nondestructive assessment of thickness and weld condition on a steel stack and liner
• Nondestructive assessment of FRP liners
• For concrete or brick chimneys, installing crack monitoring equipment