DWO Safety Procedures 3 — Questions and Answers
Question 1: What is the minimum number of independent means of escape required from each machinery space under SOLAS?
- One
- Two (Correct answer)
- Three
- Four
Correct answer: Two
SOLAS requires at least two means of escape from each machinery space to ensure crew can evacuate if one route is blocked.
Question 2: During a fire in the cargo hold, the OOW should FIRST ensure which action is taken?
- Flood the hold with CO2 immediately
- Sound the general alarm and notify the master (Correct answer)
- Deploy all firefighting teams without waiting for orders
- Ventilate the hold to reduce smoke
Correct answer: Sound the general alarm and notify the master
Sounding the general alarm and alerting the master initiates the emergency response organization before any other actions.
Question 3: A 'closed circuit' breathing apparatus (SCBA) differs from open-circuit SCBA primarily because it:
- Filters ambient air for use
- Recirculates exhaled gas, extending duration (Correct answer)
- Uses pure nitrogen to suppress fire
- Is only rated for CO2 atmospheres
Correct answer: Recirculates exhaled gas, extending duration
Closed-circuit SCBA recirculates exhaled breath through a CO2 scrubber, providing a longer air supply than open-circuit units.
Question 4: Under 46 CFR, what is the minimum freeboard deck illumination requirement during emergency drills at night?
- No specific requirement; ship's normal lighting applies
- Emergency lighting must illuminate all assembly stations and escape routes (Correct answer)
- Floodlights must be rigged over the water
- Only the bridge need be lit
Correct answer: Emergency lighting must illuminate all assembly stations and escape routes
Emergency lighting systems must ensure that assembly stations, escape routes, and survival craft embarkation areas are adequately illuminated.
Question 5: Which signal on a ship's whistle indicates 'abandon ship' when used in an emergency?
- One prolonged blast
- Five or more short and rapid blasts (Correct answer)
- Three long blasts followed by three short blasts
- The general alarm bell only; whistles are not used
Correct answer: Five or more short and rapid blasts
The abandon ship signal is more than six short blasts followed by one long blast on the ship's whistle, often paired with the general alarm.
Question 6: When testing a CO2 total-flooding system prior to entering a protected space, what must the OOW confirm?
- The CO2 cylinders are fully charged
- The system is locked out/isolated and space is properly ventilated before entry (Correct answer)
- The system can be triggered remotely from the bridge
- All personnel are inside the space to test effectiveness
Correct answer: The system is locked out/isolated and space is properly ventilated before entry
Before entering a CO2-protected space, the system must be isolated to prevent accidental discharge, and the space must be thoroughly ventilated.
Question 7: What does a 'Permit to Work' (PTW) system help control on a vessel?
- Watch scheduling and rest hours
- Hazardous tasks by ensuring risk assessment and authorization before work begins (Correct answer)
- Cargo loading sequences
- Port state control inspections
Correct answer: Hazardous tasks by ensuring risk assessment and authorization before work begins
A PTW system ensures that high-risk tasks such as hot work, confined space entry, and work aloft are formally assessed and authorized.
DWO Safety Procedures 3
What is the minimum number of independent means of escape required from each machinery space under SOLAS?