When should you not conduct an air test on a tank?

Conducting an air test on a tank that has previously contained flammable or combustible liquids is not advisable due to the significant safety risks involved. These tests involve pressurizing the tank with air to check for leaks, and if flammable vapors are present, the risk of ignition and explosion is heightened. Ensuring a safe testing environment is paramount, and using air tests on tanks that contained substances known for their flammability poses unacceptable hazards.

In contrast, while an empty tank that has contained water or has undergone recent repairs may require additional precautions, it does not inherently present the same level of danger as a tank with flammable liquids. Windy weather may affect the effectiveness of the test but is not a definitive reason to forgo testing entirely. Thus, avoiding air testing on tanks that previously held flammable or combustible liquids is crucial for upholding safety standards in UST management practices.