AST coating: required in California, extends tanks’ lives everywhere

Those bright white aboveground storage tanks (AST) haven’t been freshly painted to give them curb appeal, although they may be more pleasant to look at. The white paint – direct-to-metal (DTM) urethane, actually – adds a layer of safety to protect the environment from the tank’s contents.

The California Air Resources Board’s (CARB) Standing Loss Control Requirements include the coating of gasoline ASTs with white, high-performance paint, specifically, to keep them cooler. Doing so reduces the amount of vapors the tanks’ contents produce and how much vapor escapes.

New ASTs installed in California now meet this requirement. However, owners/operators of older tanks do not need to apply the white paint until their coatings begin to corrode with rust, chalking and/or fading. ASTs need a new coating every 10 to 20 years, depending on environmental factors. Those near the ocean, like in California, are exposed to salt water in the air, speeding up the corrosion process. Tanks in dryer climates, like the desert, will not rust as quickly.

Call a CGRS Expert:

Niko Retes
Project Manager
Refined Fuels CA
Office: 916.991.1100

Call a CGRS Expert:

Bo Bowman, P.E.
Senior Engineer
Mobile: 720.653.0213

Although other states don’t have the same requirements as California, coating ASTs is necessary to prevent corrosion and leaking, and using a high-performance paint will have the added benefit of reducing pollution and vapor loss. Rust the size of a pinpoint can spread at a rapid rate, eventually allowing vapor or fluid to escape. Painting the tank with a DTM urethane will prolong the tank’s life.

The standard cure time for the coating is about 24 hours, depending on weather conditions, before applying warning and content-identifying placards and labels to ASTs. The tanks can remain in service throughout the coating process.

If your ASTs are rusting, chalking or fading, it may be time for a new coat. Call 800.288.2657 to schedule an inspection by one of our tank experts like CGRS Project Manager Niko Retes, a (NACE) Level 2 Coatings Inspector.

For more information about CARB’s Standing Loss Control Requirements, visit