On offshore drilling units, the fire main system must have enough fire hydrants so that each accessible space may be sprayed with at least __________.

Correct Answer: Option B — two spray patterns

Per 46 CFR 108.415, the fire main system on a mobile offshore drilling unit must be equipped with sufficient hydrants positioned so that any part of an accessible space can be reached by at least two spray patterns. Each pattern must originate from a separate hose attached to a distinct fire hydrant.