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Critical Ship Equipment- Working on Critical Systems

If a sudden operational failure of equipment or technical systems on board may result in a hazardous situation, that equipment or system is considered critical. Master and Chief Engineer must draw up a list of Critical Ship Functions and Critical Equipment (Main and Standby). These Critical Lists are to be formalised on board and sent to the office.

The agreed list of Critical Equipment must be accurately reflected and identified in the vessel’s PMS.This list will always include; Supply of electrical power to essential services, Propulsion, Steering ,Main Engine, Steering gear, Generators

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Critical Ship Functions
The list of critical ship functions may also include ship specific functions, for example the capability to recover from a semi-submerged condition for a heavy-lift vessel.

Critical Stand-By Equipment
Working from the basis of the critical machinery list, a list of critical stand-by arrangements should be drawn up. The critical stand-by arrangements list should be decided using the criteria of “Will a single critical stand-by arrangement failure compromise one of the critical machinery functions”.

The critical stand-by arrangement list will generally include:
  1. Electrical Generating Plant
  2. Main Air Compressor Sets
  3. Control Air Compressor Sets
  4. Main and Auxiliary Engine circulating systems pump sets
  5. Main Engine Electrical Blower
  6. Main Switchboard and Components
  7. Main and Auxiliary Engine system filters
  8. HFO & LO pumps
  9. Feed Water System Pump Sets
  10. Boiler Circulating Pump Sets
  11. Boiler Water Gauge Glass Sets
  12. Boiler Safety Valve Sets
  13. Steering Gear Pump Sets
  14. Rudder, Shafting and Propeller systems
  15. Control engineering items
  16. Ships Side Valves
  17. Windlass and Mooring Sets
  18. High and Low Level Alarms
  19. Stand-by Whistle, Siren Horn etc
  20. Critical Idle Functions (Equipment which is safety critical but not in day-to-day use).
  21. Quick closing valves, Remote stops and switches
  22. Over-speed trip arrangements
  23. First start arrangement
  24. Emergency Electrical Generating Plan
  25. Emergency Lighting
  26. Emergency Compressor
  27. Emergency Fire Pump
  28. Fire Fighting and Detection Systems
  29. Safety and Lifesaving Equipment
  30. B.A. Compressor
  31. Emergency Steering Arrangement
  32. Main & Auxiliary Engine Shutdown arrangements.

Minimum Stock Level for Critical, Spare Parts, Consumables and Tools

It is the responsibility of the Chief Engineer to set the minimum level stock listing, customised for each vessel and to formally agree with the Fleet Superintendent the contents of the list.

The Chief Engineer must then maintain the agreed minimum stock levels and to ensure, as appropriate, the necessary requisitions. Deficiencies are to be brought to the attention of the Master and the technical Department of the relevant management Office as “Critical Spares Inventory Monthly Report” . This report must be completed and returned to the Managing Officer. The under-mentioned listings are the recommended Minimum Stock Levels for the items list.


Working on critical equipment and systems

Persons who are responsible for the operation, maintenance, repair of critical equipment and systems, as well as the calibration and adjustment of alarms and other parameters of the equipment, must be properly qualified, trained or experienced in the use of these crucial items. Either the Master or Chief Engineer is responsible for ensuring that the competency of the person involved in the maintenance is sufficient to carry out the task or must personally supervise critical phases of overhaul. If there is any doubt as to the ability and competence of those onboard to carry out a particular task successfully on critical equipment or systems, then the management office must be notified for further guidance and/or instruction as to how to proceed.

Whenever routine planned maintenance of major critical equipment is to be carried out that involves shutting down the equipment, ship’s staff will consult with the management cell. A risk assessment will be required before the equipment is shut down. The risk assessment will include, but not be limited to, addressing the following topics:
  1. Alternative back-up equipment / systems.
  2. Any necessary modification in operational procedures as a result of the equipment being out of service.
  3. Any additional safety procedures (emergency equipment etc).
If the agreed out of service period for critical equipment or systems maintenance cannot be achieved, any extension or alternative actions will require review by the shore management. In additional, a further risk assessment may be required if circumstances (such as environmental conditions, crew fatigue or operational parameters) change.

Trends and historical data recorded in PMS should be used to modify the maintenance interval or critical systems, in order to prevent incidents or out of service periods that could be associated with a failure.


Ordering Critical Repairs or Spares

When any item from this list requires a spare or repair, the Requisition Form must be endorsed “Spare for Critical Equipment” marked appropriately and followed up with a telephone call, as explained in the Purchasing Section of these procedures.

It is the responsibility of the Chief Engineer to set the minimum level stock listing, customised for each vessel and to formally agree with the Fleet Superintendent the contents of the list. The Chief Engineer must then maintain the agreed minimum stock levels and to ensure, as appropriate, the necessary requisitions. Deficiencies are to be brought to the attention fo the Master and the technical Department of the relevant management Office as “Critical Spares Inventory” Monthly Report . This report must be completed and returned to the Managing Officer.


Quick Checklist (QCL)

For portable tools and equipment which are more likely to get lost or stolen, and which are costly and essential for work and running of the ship, a Q.C.L. list must be established. Include some of the items listed in the inventory for the ship, and one copy of the Q.C.L. to be forwarded to the Company.



For the Deck Department, the following similar items are included: binoculars, walkie-talkies, sextants and other mobile navigational aids, professional books supplied by the owners (e.g. Handbook, IMO dangerous goods code etc.,) large ropes, power tools, valuable entertainment equipment, typewriters, calculators etc. For the Engine Department, the following similar items are included: measuring tools, test instruments, power tools.

Such Q.C.L. is not normally to contain more than 10 to 15 items. This list must also include items which are in custody of the senior officers, such as the Chief Mate, 1st Assistant Engineer, Electrician, etc., and when there is a change of Master or Chief Engineer, the content of the list must be confirmed. The Master and the Chief Engineer are to check these items against the Q.C.L. when there is a change of officer, and report any discrepancies immediately to the Company.



Below is our guideline for working principles and operational guideline for machinery spaces:


Marine diesel engines - Main propulsion machinery

Steam generating plant -Boiler arrangements

Feed systems for auxiliary boilers and steam turbines

Steam turbines - Energy conversion process

Other marine auxiliary machinery

Fuel oil & lub oil treatment & centrifugal process

steering gear arrangement, testing & regulatory requirement

Pumps and pumping arrangement

Valves and pipelines for machinery spaces

Refrigeration of cargo spaces and storerooms

Heating, ventilation & air conditioning

Propeller shaft arrangement

Power generation , supply & distribution system

Deck machineries & cargo gears

Control and instrumentation

Fire protection

Engine room safety


Marine machineries - Useful tags

Marine diesel engines ||Steam generating plant ||Air conditioning system ||Compressed air ||Marine batteries ||Cargo refrigeration ||Centrifugal pump ||Various coolers ||Emergency power supply ||Exhaust gas heat exchangers ||Feed system ||Feed extraction pump || Flow measurement || Four stroke engines || Fuel injector || Fuel oil system || Fuel oil treatment ||Gearboxes || Governor || Marine incinerator || Lub oil filters || MAN B&W engine || Marine condensers || Oily water separator || Overspeed protection devices || Piston & piston rings || Crankshaft deflection || Marine pumps || Various refrigerants || Sewage treatment plant || Propellers || Power Plants || Starting air system || Steam turbines || Steering gear || Sulzer engine || Turbine gearing || Turbochargers || Two stroke engines || UMS operations || Drydocking & major repairs || Critical machinery || Deck machineries & cargo gears || Control and instrumentation ||Fire protection ||Engine room safety ||





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