When using a high-velocity fog stream in a passageway, the possibility of a blow back must be guarded against. Blow back is most likely to occur when __________.
A
the only opening in a passageway is the one from which the nozzle is being advanced
B
a bulkhead collapses due to heat and pressure
C
pressure builds up in the nozzle which causes a surge of water
D
pressure in the fire hose drops below 100 psi
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Question 1 / 2066636eec28f7522a1c51d052
Question 1 of 2066636eec28f7522a1c51d052
When using a high-velocity fog stream in a passageway, the possibility of a blow back must be guarded against. Blow back is most likely to occur when __________.
When using a high-velocity fog stream in a passageway, the possibility of a blow back must be guarded against. Blow back is most likely to occur when __________.