SUPPLY LAYS

Question 0

Race for water

Answer 0

Engine is within 150 feet of a hydrant

No lay required

Question 1

Supply lays

Answer 1

Forward supply-hydrant to the fire
Reverse lay 
Split lay
Dual supply
Tandem supply

Question 2

Forward lay

Answer 2

First in engine lays from hydrant to the fire
Hydrant is adequate second in engine is delayed
Hydrant unsupported

Question 3

First engine forward lay second engine pumps hydrant

Answer 3

Typical set up

Question 4

Estimations on capability of supply lays

Answer 4

Single 3" supply 500 GPM
Single 4" supply 1000 GPM
Dual supply 1500 GPM
Tandem supply 500 GPM
Split lay 1000 GPM

Question 5

Friction loss per hundred feet

Answer 5

3 inch at 500 GPM 18 PSI per 100’
4 inch supply at 1000 GPM 15 psi per 100’
4 inch supply at 500 GPM 4 PSI per 100’
Dual supply at 1500 GPM 16 PSI per 100’

Question 6

Typical residual pressure from hydrant

Answer 6

50 to 100 psi

Typically not capable of providing 500 GPM through 200 to 300 feet of hose without supporting the 4 way

Question 7

Establishing a water supply

Answer 7

Attack engine laid supply lines- tell supply engine PDP
Supply engine laid supply lines- tell supply engine anticipated GPM
Supporting unknown flows:
3” 100 psi
4” 50 psi