单选题Which of the following statements is true concerning Halon 1301 fire extinguishing equipment?（）AThe agent is considered nontoxic at room temperature in low concentrationsBThe agent is less effective than carbon dioxideCHalon primarily extinguishes the fire by coolingDThe agent cannot be used on electrical fires because it leaves a residue
单选题
Which of the following statements is true concerning Halon 1301 fire extinguishing equipment?（）
A
The agent is considered nontoxic at room temperature in low concentrations
B
The agent is less effective than carbon dioxide
C
Halon primarily extinguishes the fire by cooling
D
The agent cannot be used on electrical fires because it leaves a residue
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