What is osmosis in a GRP (fibreglass) hull, and what are the classic early signs to look for?

A. A cosmetic issue affecting only the deck, never below the waterline

B. Water gradually permeating through the gelcoat into the underlying laminate, reacting with residual chemicals to form a mildly acidic solution that draws in more water and can create small blisters — small, weeping blisters in the gelcoat below the waterline, sometimes with a vinegar-like smell when pierced, are the classic early sign

C. A structural defect that only occurs in wooden-hulled vessels

D. A problem that resolves itself permanently once a hull is lifted out of the water for a single season

A. Nothing — a test lift can proceed immediately after repairs

B. Testing should wait until cargo operations begin

C. The area within the grab's swing radius should be cleared of personnel before the lift

D. Only the crane operator needs to be aware the lift is happening

A. Who must remain clear of the exclusion zone while the lift takes place

B. The lunch schedule for the deck team

C. Only the weather forecast for the next watch

D. The cargo manifest for the next port