4.1 Marking of cargo tanks
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC.1/Circular.1401 – Guidelines on Tank Entry for Tankers Using Nitrogen as an Inerting Medium – (9 June 2011) - Annex – Guidelines on Tank Entry for Tankers Using Nitrogen as an Inerting Medium - 4 Initial Preparation - 4.1 Marking of cargo tanks

4.1 Marking of cargo tanks

  4.1.1 Tanks should be clearly marked to make it clear to all which are safe for entry and which must not be entered. Any tank where crew are working should be clearly marked as such.

  4.1.2 Warning signs should also be posted at the gangway, and at other locations as deemed necessary by the master, when nitrogen is being produced on board or received from shore.

  4.2 After a tank has been cleaned and ventilated, the following steps should be taken:

  4.2.1 Ensure that the tank to be entered has been segregated from all other spaces which contain or may contain a non-gas free atmosphere. All common line valves should be lashed in the closed position and labelled.

  4.2.2 Check that all cargo pipes in the tank being entered have been flushed and drained.

  4.2.3 In addition to the safety equipment used for tank entry, rescue and resuscitation and fire-fighting equipment should be available, inspected and in proper working order. This may include the following:

  • .1 equipment to be immediately available on deck:

    • .1 rescue hoist equipment to enable an injured person to be removed from the tank;

    • .2 self-contained breathing apparatus;

    • .3 oxygen meter;

    • .4 gas meter; and

    • .5 toxic gas detector;

  • .2 equipment to be carried on board and readily available:

    • .1 stretchers;

    • .2 resuscitator;

    • .3 first-aid kit;

    • .4 fire hose with spray nozzle; and

    • .5 dry chemical and foam fire extinguishers;

  • .3 equipment for each member of the tank entry party: flashlight and protective clothing; and

  • .4 equipment to be carried by at least one member of the tank entry team: intrinsically safe two-way portable radiotelephone apparatus.

  4.2.4 The attendant should stand by the tank entrance while people are in the tank. In addition, sufficient people to form a rescue team should be identified, readily available and should not be involved in the tank entry.

  4.2.5 Establish a means of communication and emergency signals between the persons on deck and the persons in the tank. Ensure everybody understands these signals before tank entry and ensure that intrinsically safe two-way portable radiotelephone apparatus is available for the use of the attendant at the tank entrance.

Parent topic: 4 Initial Preparation
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