TB #7 FIGHTING FIRES WIHT LARGE SPRAY STREAMS

Question 1

WHAT ARE THE DIFFERENCES BETWEEN SPRAY STREAMS AND STANDARD STRAIGHT STREAMS?

Answer 1

SIZE OF THE WATER DROPLETS, SHAPE OF THE STREAM AND EFFECTIVE REACH

Question 2

WHAT ARE THE FACTORS MOSTLY CONCERNED WITH THE EFFICIENCY OF EXTINGUISHMENT BY WATER SPRAY ARE?

Answer 2

SURROUNDING TEMPERATURES, PHYSICAL CONDITIONS OF THE FIRE AREA, AND SIZE AND ENERGY OF THE WATER DROPLETS

Question 3

WATER EXPANDS INTO STEAM AT A RATIO OF __.

Answer 3

1 TO 1700

Question 4

1 GALLON OF WATER IS CAPABLE OF PRODUCING ABOUT ___ CUBIC FEET OF VAPOR.

Answer 4

227

Question 5

1 GALLON OF WATER ABSORBS __ BTU IN CHANGING TO STEAM WITH ONLLY __ OF THESE BUT’S BEING UTILIZED IN RAISING THE WATER TEMPERATURE FROM 62 TO 212 DEGREES F.

Answer 5

9330, 1250

Question 6

WHAT ARE THE ADVANTAGES OF SPRAY STREAMS?

Answer 6

• GREATER SURFACE AREA
• MORE EFFICIENT USE AND LESS WATER DAMAGE
• SMALLER WATER DROPLETS CAN MORE RAPIDLY BE CONVERTED INTO VAPOR (STEAM)
• SHIELDING PERSONNEL FROM RADIANT HEAT
• GREATER COVERAGE WITH LESS NOZZLE MOVEMENT
• EASILY MANAGED
• USED MORE ADVANTAGEOUSLY AND EFFECTIVELY ON FLAMMABLE LIQUID AND ELECTRICAL FIRES

Question 7

WHAT ARE THE DISADVANTAGES OF SPRAY STEAMS?

Answer 7

• LESS REACH DUE TO FRICTION
• SKIN FRICTION
• EXTREME FINENESS OF SPRAY STREAMS EVEN AT HIGHER PRESSURES
• SMLLER DROPS EASILY DISTURBED
• VENTILATION AND WIND CURRENTS REDUCE EFFECTIVENESS
• LARGE FIRE MAY DEMAND LARGE VOLUME OF WATER
• OPERATION ON HOT FIRE IN CONFINED SPACES MAY BE UNTENABLE