MFD Hydraulics
You have a static pressure of 75 and a residual of 64 what is the percentage of pressure drop?
(75-64)100 ----------- 75 1100 --------- 75 =14.6%
Calculate the pressure drop if you have a static pressure of 85 and a residual of 76. If a an engine is delivering 315 GPM how much more water can the supply provide?
(85-76)100 =900/85 =10.5% There is 945 GPM available from the water supply 10% difference allows 3x the amt being delivered.
What is the Iowa stated formula?
(LxWxH)/100=GPM at 100% involvement for storage facility or warehouses.
What is the formula for calculating additional water available from a hydrant?
(static-residual)100 ___________________________ Static
The C for two 3" siamesed lines is?
.2
Three 2 1/2" line siamesed together will have a cefficient of?
.22
The C for one 2 1/2" line and one 3" line siamesed is?
.3
In the field you can multiply by what to get the NR for a fog nozzle?
.5
What is C for 5" LDH
0.08
The C for two 3" lines and one 2 1/2" line siamesed is?
0.12
The C for two 2 1/2" lines and one 3" line siamesed is?
0.16
The C for two siamesed 2.5" lines is?
0.5
What is C for 3" handline?
0.8
What rule of thumb is followed for supplying a standpipe?
1-10 floors 150 PSI at the siamese Above 10 floors 200 PSI at the siamese
How much psi is added to appliances, IE wye, Siamese, water thief?
10 psi
Most Fog nozzle standard PSI?
100
Upon arrival to a call for a house fire you find a 2 story residence with a working fire present on the first floor only. It appears to be 20% involved and the structure is 30x30, how GPM are needed?
120 GPM (30x30)/3=300 300x0.2=60 60x2=120
What is C for 1 3/4" hose
15.5
coefficient for 1" hose?
150
Rule of thumb for supplying sprinkler system less than one block?
150 PSI
AFFF Eductor 2 1/2" set inlet pressure at?
150-200 PSI
GPM needed for a 3 story residence that is 60% involved and is 50x50?
1500 GPM (50x50)/3=833.33 833.33x0.6=500 500x3=1500
What is C for 2 1/2" hose
2
If you are supplying a sprinkler system above 10 stories what is the rule of thumb for PSI?
200
AFFF Eductor 1 1/2" set inlet pressure at?
200 PSI
If you apparatus is more than one block from a high rise structure what do you set your initial PDP at?
200 PSI
GPM needed for a 30 by 45 shed at 50% involvement
225 GPM (30x45)/3=450 450x0.5=225
C for 1 1/2" hose
24
How much pressure loss should be allowed for a standpipe system?
25 PSI
When using an aerial device how is friction loss calculated?
25 PSI is added for internal piping and elevation pressure loss is calculated separately.
How many GPM are added for exposures?
25% for uninvolved stories on a structure, and 25 % per adjacent exposures.
GPM needed for a 25 by 30 single story house at 100% involvement
250 GPM (25x30)/3=250
You arrive to a fire and see a medium sized shop approximately 40x50 in size with heavy smoke showing and 40% involvement of the structure, how many GPM are needed?
265 GPM (40x50)/3=666.67 666.67x0.4=266.67
A 3 story warehouse with a working fire on the second floor is 10% involved. The structure is 80x80x30 how many GPM are needed for suppression?
288 GPM (80x80x30)/100=1920 1920x0.1=192 192x0.25=48 48x2=96 192+96=288GPM
How much water pressure is available from a hydrant when there is 11-15% drop?
2x the amount being delivered
GPM needed for a one story single family dwelling, at 30% involvement and is 45 by 60?
300 GPM (45x60)/3=900 900x0.3=300
A water storage facility is 50% involved and is 300x100x20, no exposures, how many GPM are needed?
3000 GPM (300x100x20)/100=6000 6000x0.5=3000
GPM needed for a 50x25 single story residence at 75% involvement
310 GPM (50x25)/3=416.67 416.67 x .75=312.5
Friction loss through appliances will be considered insignificant if flowing less than _____GPM.
350
How much water is available from a hydrant if there is 0-10% drop?
3x the amount being pumped
In "fire resistive" multistory buildings how many floors above the fire floor are considered as exposures and ?
4
Smooth Bore hand line Standard PSI
50
You are pumping 2 hand lines. Your gauges show that you have 60 psi static pressure and 30 psi residual how much pressure is available from the hydrant?
50% less than what is being delivered
What is the standard Nozzle pressure for HVLP fog nozzles
50psi/150gpm
What formula is used to determine elevation pressure gain or loss in a multistory building?
5x number of floors subtracting the first floor
A 100x50x16 warehouse is 75% involved with no exposures how many GPM are needed?
600 GPM (100x50x16)/100=800 800x0.75=600
A 60x20 structure @ 100% involvement with two exposures requires how many GPM?
600 GPM (60x20)/3=400 400x0.25=100 100x2=200 200+400=600
A Frac pump warehouse has a working fire at 25% of the building. It is 200x65x15 with an exposure on its Charlie side, that is a chemical storage facility, not yet involved, how many GPM are needed for this fire?
610 GPM (200x65x15)/100=1950 1950x0.25=487.5 487.5x0.25=121.88 487.5+121.88=609.38
GPM needed for a 2 story house that measures 30x40 and is 80% involved?
640 GPM (30x40)/3=400 400x0.8=320 320x2=640
GPM needed for a 2 story house that is 25x35 at 90% involvement with an exposure?
656.23 GPM (25x35)/3=291.67 291.67x0.9=262.49 262.49x2=524.98 524.98x0.25= 524.98+131.24=656.23
What numbers are utilized as the √ for GPM in SB nozzle? Handline/Maaster
7/9
What is C for 2" hose
8
Standard PSI master stream smooth Bore nozzle?
80
What method of calculating Elevation pressure gain or loss is used when dealing with fire ground geography?
Elevation pressure in PSI= 0.5xft
Two 3" lines and one 2 1/2' line at 300' flowing 600 gpm are siamesed together what is the FL?
FL= .12x36x3+10 FL=12.96 +10 FL=22.96
What is the FL formula for Siamese lines?
FL= CxQ^2xL+A+-E
What is the friction loss formula?
FL= CxQ^2xL+A+/-E
There are 800' of 5" laid from a hydrant. You're flowing 750 GPM, how much friction loss is there?
FL=.08x56.25x8 FL=36
A pair of 3" lines flowing 400gpm through a siamese at 200' in length will have how much friction loss?
FL=.2x16x2+10 FL=16.4 psi
You are supplying a sprinkler system on the 5th floor of a building with two 3" lines that are 100'. you are currently flowing 450 GPM, determine the FL.
FL=.2x20.25x1+25+20 FL=49.05
You are receiving water from a hydrant through two 3" lines siamesed into your engines intake. The lines are 400' long flowing 900 GPM and the hydrant is located 50' above your engine what is the FL?
FL=0.2x81x4+10-25 FL=16.2x4+10-25 FL=64.8=10-25 FL=74.8-25 FL=49.8 or 50 PSI
An engine is located at the base of an incline with a structure fully involved 80' above the engines position. They are flowing a single 2" line at 150 GPM through a fog nozzle with 200' deployed. What is the FL and PDP
FL=8x2.25x2+40 FL=76 PDP=NP+TFL PDP=100+76 PDP=176
What does each letter represent in the friction loss formula?
FL=Friction loss C=coefficient of the hose Q^2= GPM represent as (Q^2)/100 L=Length of hose lay divided by 100 A= Appliances E= elevation gain or loss
Friction loss per 100' of hose must be based on what when supplying a stand pipe?
GPM
What is the GPM formula for SB nozzle?
GPM= C x D^2 x √P GPM=29.7 x D^2 x √50
A 25x40 residence of 30% involved, and 1 exposure on the delta side. You have one 2 1/2" line deployed at 200' with a fog nozzle what would your PDP be?
GPM=(25x40)/3 333.33x.3=100 GPM=100+25% GPM=125 FL=2x1.56x2 FL=6.25 PDP=106.25 PDP=106.25
A 1 1/8 SB nozzle on a handline will produce how many GPM?
GPM=207.9 x 1.27 GPM = 264
a Handline has a SB tip that is 1 7/8" in size, how many GPM can it flow?
GPM=207.9x 3.52 GPM=731.8
Your engine is flowing 120 PSI through a master stream equipped with a SB nozzle that is 2" what is its GPM?
GPM=267.3 x 4 GPM=1069.2
Calculate the GPM for a master stream SB nozzle that is 2 1/2".
GPM=267.3 x 6.25 GPM = 1670.63
A handline with a 7/8" nozzle has a GPM of?
GPM=29.7 x .875 x 7 GPM=25.987 x 7 GPM=181.91
A SB with 1 1/8" tip on a master stream flows how many GPM?
GPM=29.7 x 1.25 x 9 GPM=37.125 x 9 GPM= 334.12
The GPM formula for SB can be simplified to what?
Handline GPM=207.9 x D^2 Master GPM=267.3 x D^2
If there is a pressure drop of greater than 25% when pumping, how much water pressure is available from a hydrant?
Less than what is being delivered
You arrive to a fire scene to find a 50x55 single story house 40% involved. What formula would you use to find GPM necessary for extinguishment. How many GPM do you need?
LxW/3 (50x55)/3=916.66 2750x0.25=366.67 366.66 GPM
What is the formula to determine GPM needed on residential single story fires at 100% involvement?
Multiple the length by the Width then divide by three
How is GPM determined for multistory buildings when using the Fire Flow Formula?
Multiply the GPM by the number of stories
What is the NR formula for a fog nozzle?
NR= .0505 x Q x √NR Simplified NR=.0505 x Q x √100 NR=.0505 x Q x 10 NR= .505 x Q
IF you have a Blitz fire delivering 444 GPM what is its NR?
NR= 0.505 x 444 NR= 224.22
A Fog nozzle is delivering 320 GPM to a pallet fire, what is its nozzle reaction?
NR= 0.505x 320 NR=161.3
You are operating a 1 3/4" handline with 1 3/8" smooth bore nozzle. It has 82 PSI being delivered, what is the NR?
NR= 1.57 x 1.89 x 82 NR= 2.97 x 82 NR= 243.54
Find the NR of a fog nozzle at 160 GPM.
NR=.505 x 160 NR=80.8
A working fire is being slayed by your crew. you have two 2 1/2 lines each flowing 275 GPM. They both have fog nozzles attached what is their NR?
NR=0.505 x 275 NR= 138.88
A 1" SB nozzle is flowing 350 GPM with a nozzle pressure of 75 what is its NR?
NR=1.57 x 1 x 75 NR= 1.57 x 75 NR= 117.75
What is the formula for nozzle reaction pressure of a smooth bore nozzle?
NR=1.57 x d^2 x NP Handline simplified if 50 psi NR=78.5x D^2 Master Stream simplified if 80 psi NR=125.6 x D^2
What is the NR of a 1.25 SB nozzle on a monitor device?
NR=1.57x 1.56x 80 NR=195.94
What is the NR of a 1.5" SB nozzle on a handline?
NR=1.57x1.5^2x50 NR=3.53x50 NR= 175.63
A smooth bore handline flowing 225 GPM through an 1 3/4" line that is 150' long would require how much PDP to operate effectively?
PDP=50+(15.5x5.06x1.5) PDP= 50+117.7 PDP=167.7
What is the formula used to determine PDP?
PDP=NP+TFL
A 200' section of 1 1/2" handline is being used to protect an exposure with a 3/4" SB nozzle attached. you are flowing 250 GPM What is the NR?
SBNR= 1.57 x D^2 x NP 1.57 x 0.75^2 x 50 1.57 x 0.56 x 50 0.87 x 50 NR=43.68
If there is a 16-25% in pressure, how much additional water pressure is still available from a hydrant?
Same amount as being delivered
What appliances require an additional 25 psi be added to friction loss regardless of flow?
Snorkel, ladder pipe, standpipe and master stream
In all other building construction types besides "fire resistive" how are floors above the fire floor accounted for.
They should be considered as part of the fire problem, up to the fourth floor.
What should stand pipe systems be supplied with?
Two 3" lines
How do you calculate friction loss for a combination of lines that there is no coefficient for, or you do not know the coefficient?
Use the same friction loss formula, but divide the total GPM by the number of lines being used and use the coefficient for a single line.
How do you calculate friction loss for siamesed lines of different length, and same sized hose?
Use the same friction loss formula, divide GPM by the number of lines. Find the average of the hose length's and use it as L. Use coefficient for a single line. 2 lines one 300 one 500 AVG=(300+500)/2 AVG=400' 3 lines AVG=(200+200+200)/3 =600/3 AVG=200
How is GPM calculated on multistory fire resistant buildings?
adding 25%/floor to the GPM needed for fire extinguishment.
How do you determine elevation pressure loss for a multistory building?
multiply each story by 5, not counting the first floor.
Is the ground floor counted when supplying a sprinkler system of a multistory structure?
no
For either method of calculating elevation pressure gain/loss psi is _________________ if the nozzle below the pump.
subtracted