According to the STI AST SP001 External Tank Inspection standard, the frequency of inspections for ASTs can vary depending on several factors, including the tank's age, the material stored and local regulations. The standard provides general guidelines for inspection intervals, but the specific schedule should be determined based on a risk assessment and the conditions of the tank and its surroundings. It is critical to determine the AST category, which aids in establishing the appropriate inspection schedule and maintenance plan.
