Enclosed Space Entry

An enclosed space on a ship is one that may contain a hazardous atmosphere or lack of oxygen and has any of three characteristics: limited openings for entry and exit, inadequate ventilation, or no design for continuous human occupancy. Resolution MSC.581(110) paragraph 2.1 states the test disjunctively, which is a change from the conjunctive wording of the superseded A.1050(27) and widens the class of spaces caught. Its own examples are cargo holds, bilge spaces, ballast and other tanks, pump rooms, chain lockers and engine crankcases; cofferdams, duct keels and void spaces qualify on the same test. Entry without testing the atmosphere remains one of the most persistent causes of multiple fatalities at sea. The operational procedure is covered in full at enclosed space entry and tank inspection .

The full article will cover the mechanisms that make these spaces dangerous, including oxygen depletion by rusting steel and by wet organic material, cargo off-gassing, and inerting residue, and why the second and third casualties are usually would-be rescuers who entered without breathing apparatus. It will cover the permit to work system, atmosphere testing sequence, continuous monitoring, the standby person, and rescue arrangements.

It will also cover the enclosed space entry and rescue drill requirement under SOLAS, and the design responses that reduce the need for entry at all, such as arranging a chain locker bitter end slip for release from outside the space.