CO2 not used by itself on a major fire and sisal line poor; which statement is correct?

CO2 not used by itself on a major fire and sisal line poor; which statement is correct?

• A. CO2 should not be used by itself on a major fire, and sisal line shock absorption is poor.
• B. CO2 should be used by itself on a major fire, and sisal line shock absorption is poor.
• C. CO2 should be used by itself on a major fire, and sisal line shock absorption is excellent.
• D. CO2 should not be used by itself on a major fire, and sisal line shock absorption is excellent.

Answer: (B)

The test is checking two practical truths about shipboard fire control and line performance: how CO2 behaves as an extinguishing agent and how a sisal line handles shock. CO2 floods a space and can suppress a fire by displacing oxygen, so in a major fire in an enclosed area it is appropriate to use CO2 as the primary extinguishing measure when conditions allow safe evacuation of personnel and control of the space. At the same time, sisal rope is a natural fiber with relatively low stretch, meaning it does not absorb much energy under load, so its shock absorption is poor compared with modern synthetic lines. Put together, the statement that CO2 should be used by itself on a major fire and that sisal line shock absorption is poor aligns with these known behaviors, making it the best choice. The other options conflict with either how CO2 works in a major fire or the actual performance characteristics of sisal line.

The test is checking two practical truths about shipboard fire control and line performance: how CO2 behaves as an extinguishing agent and how a sisal line handles shock. CO2 floods a space and can suppress a fire by displacing oxygen, so in a major fire in an enclosed area it is appropriate to use CO2 as the primary extinguishing measure when conditions allow safe evacuation of personnel and control of the space. At the same time, sisal rope is a natural fiber with relatively low stretch, meaning it does not absorb much energy under load, so its shock absorption is poor compared with modern synthetic lines. Put together, the statement that CO2 should be used by itself on a major fire and that sisal line shock absorption is poor aligns with these known behaviors, making it the best choice. The other options conflict with either how CO2 works in a major fire or the actual performance characteristics of sisal line.