USCG Exam PracticeHydraulics and pneumatics
A hydraulic system aboard a commercial fishing vessel loses pressure suddenly. Which regulatory requirement is specifically intended to prevent uncontrolled movement of hydraulically operated machinery in this situation?
- A. The system must be equipped with a pressure relieving device set to the maximum operating pressure.
- B. Piping must have a burst pressure of four times the maximum operating pressure.
- ✓ The machinery must be equipped with a holding device or be fail-safe to prevent uncontrolled movement.Correct
- D. Controls must be located where the operator has an unobstructed view of the equipment.
Why C is correct
46 CFR §28.880(g) requires that hydraulically operated machinery be fail-safe or equipped with a holding device to prevent uncontrolled movement or sudden loss of control due to loss of hydraulic system pressure. The pressure relieving device (option A) protects against overpressure, not loss of pressure. Burst pressure (option B) addresses piping integrity, and operator sightlines (option D) address control placement.
Cited:46 CFR §28.880