The minimum backfilled cover for buried piping may be reduced to 18 inches where physical damage is prevented. Which of the following reflects that rule?

The minimum backfilled cover for buried piping may be reduced to 18 inches where physical damage is prevented. Which of the following reflects that rule?

• A. 18 inches
• B. 20 inches
• C. 24 inches
• D. 16 inches

Answer: (A)

Protecting buried piping from physical damage lets you use a shallower burial depth. When effective physical protection is in place, the minimum backfilled cover can be reduced to 18 inches. This reflects the allowance that the risk of surface damage is mitigated by safeguards, so depth can be less while still maintaining safety. Therefore, 18 inches is the correct depth. The other options aren’t the allowed reduced depth: they are either deeper than the stated exception or shallower than the protection permits.

Protecting buried piping from physical damage lets you use a shallower burial depth. When effective physical protection is in place, the minimum backfilled cover can be reduced to 18 inches. This reflects the allowance that the risk of surface damage is mitigated by safeguards, so depth can be less while still maintaining safety. Therefore, 18 inches is the correct depth. The other options aren’t the allowed reduced depth: they are either deeper than the stated exception or shallower than the protection permits.