Full Ism Manual
Appendix B – Critical Equipment
Identification and evaluation of critical equipment on board the yacht.
Identification
- Criticality for equipment is defined as: “the sudden operational failure of which may result in hazardous situations”, and is therefore specific to vessel type and design.
- Critical equipment is identified in the vessel maintenance programme.
- Level of risk considerations:
- Threat to life (from negligible injury through to multiple fatalities)
- Threat to the environment (from minor pollution through to major pollution)
- Likelihood of occurrence
- Frequency of use of the equipment
- Redundancy of the equipment (equipment that is redundant is less critical in case of failure; equipment designed to activate in case of failure is already a back‑up)
- Ease of testing and maintaining the equipment
- Weather influence in case of breakdown
- Be as specific as possible when relating to equipment. For example, consider not only “the crane” but also “the crane cable”, “the crane lifting system”, “the crane limiting switches”, etc.
Evaluation criteria
- In general, all equipment supplying and supplied by the emergency switchboard should be considered.
- Safety equipment that is not redundant. For example: Emergency Escape Breathing Device (EEBD), fire dampers, quick‑closing valves, emergency stops, Man‑Overboard (MOB) rescue boat, fire central detection, carbon‑dioxide (CO₂) systems, watertight sliding‑door remote‑closing system, oil‑mist detector, alarm systems, etc.
- Anti‑pollution equipment that is not redundant. For example: 15‑ppm alarm cell, deck connections.
- Watertight integrity protection.
- Navigational communications equipment, including sound and light signalling systems.
- Emergency power supplies, including batteries.
- Fuel systems, including emergency stops and quick‑closing valves.
- Fire, gas, and heat detection systems.

