Most Port State Control detentions do not come from one dramatic failure. They come from an accumulation of small, visible things — an expired certificate, a lifeboat engine that will not start, a fire door lashed open — that together tell an inspector the vessel is not being maintained.
Start with the paperwork Certificates are the first thing opened and the easiest thing to fix in advance. Two weeks before the call, list every certificate falling due within three months and confirm each renewal is either done or booked. Liferaft servicing, extinguisher inspection, breathing apparatus and lifting gear are the ones most often left to the last week.
Then the things that get switched on Inspectors ask crew to operate equipment, not describe it. Emergency generator on load, emergency fire pump, lifeboat and rescue boat engines, quick-closing valves, watertight doors and general alarm — each of these should be run by the crew who would run it in an emergency, before the inspection rather than during it.
Look at the vessel the way a stranger would Walk the deck and accommodation as if you had never seen them: oil in the bilges, missing guard rails, blocked escape routes, gauges that read zero, garbage segregation that does not match the placard. These are the observations that shape an inspector's judgement before a single record is opened.
Have the records ready, not just correct Oil record book, garbage record book, hours of rest, maintenance records and drills all need to agree with each other and with what the crew says. Contradictions between records are treated far more seriously than a gap in one of them.
If a deficiency is raised anyway, the practical response is the same as any repair: get it inspected properly, get a written scope, and close it out with documentation the next inspector can read.