Which designation corresponds to a tank built to haul flammable liquids, combustibles, Class B poisons, and liquid foods with vapor pressures up to 4 psi?

Which designation corresponds to a tank built to haul flammable liquids, combustibles, Class B poisons, and liquid foods with vapor pressures up to 4 psi?

• A. MC 306/DOT 406
• B. MC 307/DOT 407
• C. MC 312/DOT 412
• D. MC 331/DOT 407

Answer: (A)

Understanding how tank designations map to what they can carry helps you pick the right type. The 4 psi vapor-pressure limit is a key factor that distinguishes non-pressurized liquid cargo tanks from other tank designs. Tanks built to handle liquids with vapor pressures up to 4 psi are designated MC 306 (DOT 406). These are designed for flammable liquids, combustibles, Class B poisons, and liquid foods, where the vapor pressure remains relatively low and the tank operates without internal pressurization. Other designations correspond to different pressure ranges or cargo types, so they don’t fit the 4 psi limit. For example, designs used for higher-pressure or different-cargo service are assigned other MC/DOT designations, such as MC 307/DOT 407 or MC 331/DOT 331, and corrosives have their own type (MC 312/DOT 412). So the 4 psi limit matches MC 306/DOT 406, making it the best fit for the scenario.

Understanding how tank designations map to what they can carry helps you pick the right type. The 4 psi vapor-pressure limit is a key factor that distinguishes non-pressurized liquid cargo tanks from other tank designs. Tanks built to handle liquids with vapor pressures up to 4 psi are designated MC 306 (DOT 406). These are designed for flammable liquids, combustibles, Class B poisons, and liquid foods, where the vapor pressure remains relatively low and the tank operates without internal pressurization.

Other designations correspond to different pressure ranges or cargo types, so they don’t fit the 4 psi limit. For example, designs used for higher-pressure or different-cargo service are assigned other MC/DOT designations, such as MC 307/DOT 407 or MC 331/DOT 331, and corrosives have their own type (MC 312/DOT 412). So the 4 psi limit matches MC 306/DOT 406, making it the best fit for the scenario.