TL;DR — Know the five fire classes (A, B, C, D, K), match the correct extinguishing agent to each, and follow the sequence: alert crew → isolate → shut off fuel/electrical → attack → confirm → ventilate. For flooding, the priority order is stop flooding, maintain stability, save the vessel — abandon ship only when those two priorities have failed.
What the Rule Says
Fire Classification
Shipboard fires are classified by the type of fuel involved. USCG Boatswain Manual Ch. 6 §6.1 establishes five classes:
- Class A — ordinary combustible materials (wood, paper, cloth)
- Class B — flammable liquids and gases (fuel oil, gasoline, LPG)
- Class C — energized electrical equipment
- Class D — combustible metals (rare on small vessels)
- Class K — cooking oils and fats (galley fires)
The governing principle is straightforward: use the correct extinguisher class for the fuel involved. A mismatch — for example, applying water to an energized electrical fire — can be lethal.
The Firefighting Sequence
USCG Boatswain Manual Ch. 6 §6.3 prescribes a specific sequence that must be followed in order:
1. Alert the crew — sound the alarm before taking any other action. 2. Isolate the fire — close hatches and shut off ventilation to deny the fire its oxygen supply. 3. Shut off fuel and electrical to the affected space. 4. Attack with the appropriate extinguisher. 5. Confirm extinguished. 6. Ventilate carefully to prevent re-ignition.
46 CFR §185.512 reinforces this sequence in the recommended emergency instruction placard format. For a fire in machinery spaces specifically, the placard directs the crew to shut off fuel supply and ventilation and activate the fixed extinguishing system if installed. The placard also specifies that portable fire extinguishers should be applied at the base of flames for flammable liquid or grease fires, or water for fires in ordinary combustible materials — and explicitly states: do not use water on electrical fires.
Additionally, the vessel should be maneuvered to minimize the effect of wind on the fire. If the fire cannot be controlled, the crew must immediately notify the Coast Guard and other craft in the vicinity by radiotelephone, move passengers away from the fire, have them don life jackets, and if necessary prepare to abandon the vessel.
Damage Control Priorities
USCG Boatswain Manual Ch. 5 §5.1 establishes three damage control priorities for small vessels, in strict order:
1. Stop the flooding. 2. Maintain stability. 3. Save the vessel.
If priorities 1 and 2 cannot be achieved, the order is to abandon ship. The vessel is never abandoned as a first resort.
provides complementary flooding response steps on the emergency instruction placard:
- Close all watertight and weathertight doors, hatches, and airports to prevent taking water aboard or further flooding.
- Keep bilges dry to prevent loss of stability due to water accumulation; use power-driven bilge pump, hand pump, and buckets to dewater.
- Align fire pumps to use as bilge pumps if possible.
- Check all intake and discharge lines that penetrate the hull for leakage.
- Passengers must remain seated and evenly distributed.
- Passengers must don life jackets if conditions become very rough, the vessel is about to cross a hazardous bar, or when instructed by the master.
- Never abandon the vessel unless actually forced to do so.
- Prepare survival craft (life floats, inflatable rafts, inflatable buoyant apparatus, boats) for launching.
Crew Training Requirements
46 CFR §185.420 places the training obligation on the owner, charterer, master, or managing operator. Each crew member must be instructed:
- Upon first being employed on the vessel;
- Prior to getting underway for the first time on a particular vessel; and
- At least once every three months.
For vessels subject to the enhanced firefighting training requirement, the program must address firefighting proficiency and include, at minimum:
- Location of firefighting appliances and emergency escape routes;
- Types and sources of ignition;
- Flammable materials, fire hazards, and spread of fire;
- The need for constant vigilance;
- Actions to be taken on board;
- Fire and smoke detection and automatic systems on board; and
- Classification of fire and applicable extinguishing agents.
Emergency egress training must occur at least monthly for crew members employed on board, and each time a new crew member joins the vessel.
Training conducted on a sister vessel may be considered equivalent to the initial, monthly, and quarterly training requirements.
All crew training must be logged or otherwise documented for review by the Coast Guard upon request. The log entry must include the date of training and a general description of the training topics.
Man Overboard Response
specifies the man overboard sequence on the emergency instruction placard:
- Throw a ring buoy overboard as close to the person as possible.
- Post a lookout to keep the person overboard in sight.
- Launch rescue boat and maneuver to pick up the person in the water, or maneuver the vessel to pick up the person.
- Have a crew member put on a life jacket, attach a safety line, and stand by to enter the water to assist if necessary.
- If the person is not immediately located, notify the Coast Guard and other vessels in the vicinity by radiotelephone.
- Continue search until released by the Coast Guard.
Why It Matters on the Exam
Exam questions on this topic test three things: fire class identification, the correct extinguishing agent for each class, and the proper sequence of actions. Candidates who memorize the fire classes without understanding the sequence — or who know the sequence but cannot apply it to a specific scenario — will miss points.
The damage control priority order is a frequent exam item. The sequence from USCG Boatswain Manual Ch. 5 §5.1 — stop flooding, maintain stability, save the vessel — is tested directly. Distractors will invert the order or insert "abandon ship" prematurely.
Training frequency is another tested area. The quarterly (every three months) general crew training interval and the monthly egress training interval from 46 CFR §185.420 are both testable. Candidates confuse the two intervals; remember that egress training is more frequent (monthly) than general emergency training (quarterly).
The prohibition on using water on electrical fires appears explicitly in 46 CFR §185.512 and is a classic exam distractor — a question may offer water as a correct option for a Class C fire.
For machinery space fires, the specific step of activating the fixed extinguishing system (after shutting off fuel and ventilation) is tested.
Common Pitfalls
Pitfall 1: Confusing Class B and Class K. Class B covers flammable liquids and gases broadly. Class K is specifically cooking oils and fats in galley applications. USCG Boatswain Manual Ch. 6 §6.1 Exam questions may present a galley grease fire and expect you to identify it as Class K, not Class B.
Pitfall 2: Skipping the isolation step. The firefighting sequence requires isolating the fire — closing hatches and shutting off ventilation — before attacking with an extinguisher. USCG Boatswain Manual Ch. 6 §6.3 Candidates who jump straight to "grab the extinguisher" select the wrong answer.
Pitfall 3: Applying water to electrical fires. 46 CFR §185.512 explicitly prohibits water on electrical fires. This is a hard rule, not a guideline.
Pitfall 4: Abandoning ship too early. The damage control doctrine from USCG Boatswain Manual Ch. 5 §5.1 and the emergency placard from both state that the vessel is never abandoned unless actually forced to do so. Abandon ship is the last resort, not a precautionary measure.
Pitfall 5: Forgetting to document training. 46 CFR §185.420 requires that crew training be logged with the date and a general description of topics. Undocumented training is a deficiency during a Coast Guard examination.
Pitfall 6: Ventilating too soon after extinguishment. specifies that ventilation after extinguishment must be done carefully to prevent re-ignition. Premature or careless ventilation can reintroduce oxygen to smoldering material.
Quick Check
Q1: List the five fire classes and the type of fuel each covers.
Class A — ordinary combustibles; Class B — flammable liquids and gases; Class C — energized electrical equipment; Class D — combustible metals; Class K — cooking oils and fats (galley fires). USCG Boatswain Manual Ch. 6 §6.1
Q2: What is the correct firefighting sequence per the Boatswain's Manual?
Alert the crew → isolate the fire (close hatches, shut off ventilation) → shut off fuel and electrical to the affected space → attack with the appropriate extinguisher → confirm extinguished → ventilate carefully to prevent re-ignition. USCG Boatswain Manual Ch. 6 §6.3
Q3: What are the three damage control priorities in order?
(1) Stop the flooding. (2) Maintain stability. (3) Save the vessel. Abandon ship only if priorities 1 and 2 have failed. USCG Boatswain Manual Ch. 5 §5.1
Q4: How often must general emergency crew training be conducted, and how often must emergency egress training be conducted?
General emergency training: upon first employment, prior to first underway on that vessel, and at least once every three months. Emergency egress training: at least monthly while employed on board, and each time a crew member joins the vessel. 46 CFR §185.420
Q5: A fire breaks out in the engine room. What specific steps does the emergency instruction placard require?
Shut off fuel supply and ventilation to the machinery space, then activate the fixed extinguishing system if installed. 46 CFR §185.512
Q6: Can training completed on a sister vessel satisfy the initial and periodic training requirements?
Yes. Training conducted on a sister vessel may be considered equivalent to the initial, monthly, and quarterly training requirements.
Q7: What must a crew training log entry contain at minimum?
The date of the training and a general description of the training topics.
Q8: A crew member falls overboard and is not immediately located. What is the required notification action?
Notify the Coast Guard and other vessels in the vicinity by radiotelephone, and continue the search until released by the Coast Guard.