Inspection of aboveground storage tanks (ASTs) can be a critical compliance issue under the planning requirements of the U.S. Environmental Protection Agency’s rule for Spill Prevention Control and Countermeasure (SPCC). In 2000, the Steel Tank Institute released the first version of Standard for the Inspection of Aboveground Storage Tanks – the STI SP001 standard – which provides a means for AST owners to comply with EPA mandates. The standard has been updated by consensus of tank owners, tank manufacturers and other industry leaders.


Does the STI SP001 standard include inspection of fiberglass and other plastic tanks?

Overall, the standard focuses primarily on inspection of welded, carbon or stainless steel shop-fabricated and field-erected tanks. Also included is the inspection of smaller, portable containers such as 55-gallon drums, intermediate bulk containers (IBCs) and other such containers that may be of metal or plastic construction. Inspection of non-portable, shop-fabricated plastic or fiberglass tanks is not included. See the definitions within the standard for more specific questions related to size and material of construction. Inspection requirements for non metallic tanks can be found from the original tank manufacturer or other standards organizations.

Why does STI SP001 require internal inspections when one cannot easily access the inside of a small shop-fabricated tank?

STI SP001 does not mandate entry into a tank for any tank under 30,000 gallons (113,529 liters) for tanks identified as Category 1 per SP001 that have a mechanism for spill control, continuous release detection and overfill protection as defined in SP001. For tanks under 30,000 gallons, either internal inspections are not required, or else an alternative is given with the use of leak-test inspections. Tanks larger than 30,000 gallons usually have manways to allow personnel entry.

Where can I find the SP001 AST Record and SP001 Checklists?

The SP001 AST Record and the SP001 checklists are available to download:

Please note: the AST record and the checklists are to be used in conjunction with the SP001 Standard for the Inspection of Aboveground Storage Tanks and the utilization of the AST record and the checklists alone do not constitute compliance with STI SP001.

Joe Mentzer is the Standards Engineer for STI/SPFA and staff liaison to the STI SP001 Committee. He can be contacted at

Purchase the SP001 and SP031 standards on the STI/SPFA store.