During repairs it is necessary to replace existing vessel bulkhead. Drawings indicate the bulkhead is A60. "A" indicates which of the following?

Correct Answer: Option D — "A" class bulkheads must not allow flame or smoke passage for 60 minutes when subjected to a fire test

Under USCG National Maritime Center examination standards, the accepted correct answer is: "A" class bulkheads must not allow flame or smoke passage for 60 minutes when subjected to a fire test.