For vessels greater than 40 ft, the fatigue limit at sea state less than 4 ft is which of the following hours?

• A. 6 hours
• B. 8 hours
• C. 12 hours
• D. 10 hours

Answer: (D)

Fatigue exposure limits by sea state and vessel size are what this question assesses. For vessels greater than 40 feet, operating in very calm seas (sea state less than 4 feet) results in lower wave-induced stresses, so fatigue accumulates more slowly. The standard limit in that calm condition is ten hours of continuous operation before fatigue considerations require action, inspection, or a change in operation. The other hour values would apply to different sea-state ranges or vessel sizes, not this precise condition.