- Each slice of cheese represents a barrier to a safety threat (e.g., operator fatigue)
- Holes represent conditions that would cause a single barrier to fail in a single instance
- Multiple barriers increase the overall protection against the threat
- Incidents happen when holes line up (e.g., all barriers fail in the same instance)
The STCW code provides barriers that if effectively applied would have prevented the fatiguing conditions that contributed to the Shen Neng 1 grounding.
Section A-VIII/1 (Fitness for duty)
Section A-VIII/1 (Fitness for duty) states:
Watch systems are required to be arranged so that the efficiency of all watchkeeping personnel is not impaired by fatigue and that duties are so organized that the first watch at the commencement of a voyage and subsequent relieving watches are sufficiently rested and otherwise fit for duty.
All persons who are assigned duty as officer in charge of a watch or as a rating forming part of a watch shall be provided a minimum of 10 hours rest in any 24-hour period.
Section A-VIII/2 part 3-1 (18)
Section A-VIII/2 part 3-1 (18) states:
The officer in charge of the navigational watch shall not hand over the watch to the relieving officer if there is reason to believe that the latter is not capable of carrying out the watchkeeping duties effectively, in which case the master shall be notified.
Company policies around fatigue risk
RCCL has several policies in place concerning the monitoring and management of fatigue risk. Each policy serves as a barrier to protect against conditions that may result in watch stander fatigue and the associated performance impairment that could result in an incident.
Global Engine Policy & Procedures
Section 5.03 Fatigue Management states:
Chief Engineer / Master shall avoid operating under conditions of excessive fatigue
Section 5.05 Watch Relief states:
Arrive on the bridge / engine room with adequate time to prepare for the watch; members of the relieving watch shall be fully capable of performing their duties.
Section 10.13 Watch Schedules states:
STCW and ILO hours of rest requirements must be complied with by all deck officers at all times.
Navigation Policy & Procedures
Section 22.0 Management of Fatigue states:
Bridge Officers shall be well rested and alert before performing navigational duties.
Section 22.01 General Duties states:
Bridge Officers understand the STCW requirements for adequate rest and the Company Fatigue Policy.