Loads classified as DT or DW are to be treated as non-dimensional for meeting and passing.

• A. False
• B. True
• C. They are always forbidden in a train
• D. They require special routing

Answer: (B)

When deciding if two trains can safely meet and pass on a single-track section, certain load classifications are treated in a simplified way to keep the calculations consistent. Loads labeled as DT or DW are considered non-dimensional for meeting and passing, meaning they are not treated as adding or changing the effective weight that would alter the required clearances or timing. This convention keeps the rules uniform across different train configurations and focuses the calculations on factors like train length, speed, and standard braking distances rather than varying weight amounts.

In practice, this means these particular loads do not introduce additional constraints or routing requirements for meeting and passing decisions. They’re not forbidden or requiring special routing; they’re simply handled as dimensionless in the relevant calculations.