The Steel Tank Institute, STI, Standard for the Inspection of Aboveground Storage
Tanks, SP001, is the endorsed standard for the inspection of factory built storage
tanks listed in CFR 40 Part 112 under the SPCC regulations. The standard is risk
based which means that tanks whose failure causes greater damage to the environment
are inspected with increased frequency and detail. The inspection standard defines
the frequency and detail by three categories of risk and four categories of size.
It also specifies inspection standards and frequency for containers used to transport
In addition to defining the inspection of the tanks, it also defines the inspection
criteria for the tanks ancillary equipment, pumps, valves, vents and piping.