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Foam Durations and Densities
- i) The minimum duration is 10 min
- ii) The minimum density is .16 GPM/Sq. FT
- iii) *if density exceeds .16 gpm, the duration can be reduced to 7 minutes
- iv) *After the foam, water must last 60 minutes
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High Expansion foams
- i) Are limited to a deluge system
- ii) Installed in Aircraft hangars
- iii) Expansion rates of 2%, 2.5%, 2.75%
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E.S.F.R Heads
Need to be installed under ducts over 2’
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Max temperature of water in a sprinkler system:
120 F or 49 C
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Min size of Aux Drain:
Minimum size is ½”
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Cornice sprinklers are to be mounted:
- i) 8” below roof decking
- ii) If cornice has an overhang of more than 1 foot
- iii) Not spaced more than 10’ apart
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Max coverage area for any 1 head:
400 ft
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Can a Double-interlock preaction system be gridded?
No
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C02 Systems:
- Pipe and fittings up to ¾” are schedule 40 galvanized
- ¾”-2” are schedule 80
- Over 2” fittings are galvanized forged steel
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Low Pressure C02
- Containers are maintained at a temperature of 0 F with a pressure of approximately 300 PSI
- Storage tanks range from 500 Lbs to 125 tons
- Nozzle discharge as high as 2,500 pounds per minute
- When CO2 is released the oxygen drops from 21% to 15%
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CO2 systems
- Devices function properly in temperatures ranging from -20F to 140F
- High Pressure cylinder is maintained at 850 PSI @ 70F
- Low Pressure systems: working pressure of at least 325 PSI, supervisory alarm is set at 315 PSI and special relief valve at 250?
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Water Motor Gong
- No farther than 75’ away from the valve
- No higher than 20’
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Fire hydrant hose connection must be ___ from the ground?
18"
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Area of a triangle:
(Base X height)/2
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ABC regarding Trenches:
A ladder is required in a trench when it is 5’ or deeper. The ladder must extend 3’ above the trench
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Minimum thickness of metal you can use a power driven stud on?
3/16”
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Foam/water sprinkler system:
- Usually controlled by a deluge valve
- Difference between Foam/water sprinkler system and a Foam/Water spray system is the discharge device
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Halon NFPA 12A
- Warning signs must be inside and outside of area protected with halon
- Not allowed to deviate from engineered design
- Test semi-annually
- Tanks must be refilled if they lose more than 5% of the volume
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High pressure cylinders:
- Testing: semi-annually
- Refill if pressure dropped 10%
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High pressure systems:
Tested every 5 years but if not used and still in service it can be extended to 12 years
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Manual Pull Stations:
- No higher than 4’ from grade
- Halon pull station no higher than 5’
- Max travel: 14”
- 40 psi pulling force
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Fixed water spray systems:
Min. Sizes of pipe, steel is 1” and copper is 3”
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Max discharge rate of a fixed water spray system?
Single system not exceeding 3,000 GPM
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Can a single water supply feed more than one fixed water spray system?
YES
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Fixed water spray systems:
- Max 500 gallons per control valve
- Water supply must last 15 minutes
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If connecting antifreeze system to a potable water supply use:
Propylene-glycol
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Flushing requirements:
- Min size of flushing connection: 1 ¼”
- Min size for flushing city water supply: 2”
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When are local alarms not required?
When there are less than 20 sprinkler heads
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Small orifice heads:
3/8”, need a strainer
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Fixed water spray systems:
- Spray must meet or overlap
- Min static pressure is 50 psi
- Min operating pressure at most remote nozzle is 50 psi
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Primary design of aFixed water spray systems:
To protect the equipment 1st, then the structure
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Most effective dry chemical:
Urea potassium bicarbonate
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When is a QOD required on a Dry valve:
system is greater than 500 gallons
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Clean out on CO2 system:
Needs to be 2” long and same diameter as piping. (nipple-cap)
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CO2 systems (NFPA 12)
- Up to ¾”: sched 40 galv.
- 1” and up: sched 80 galv.
- Test: 40 PSI for 10 min (allowed 8 PSI loss)
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Fixed water spray systems:
- No bushings allowed
- Max nozzle spacing is 10 feet
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Drain sizes:
- 4” and larger: 2” drain
- 2 ½” – 3 ½”: 1 ¼” or larger
- Up to 2”: ¾” or larger
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Fixed water spray systems:
You can use copper if pressure does not exceed 175 psi
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Electronic monitoring
Every electronic device has a microswitch AKA Tamper switch
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Foam Generators
- Aspirator type:
- Produce foam with expansion ratios not over 250:1
- Blower: 250-1000
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Foam types
- Low Expansion
- 2-20
- Medium expansion
- 20-200
- High Expansion
- 200-1000
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NFPA Standards
- CO2 is NFPA 12
- Halon is NFPA 12A
- Clean agent is NFPA 2001
- Flammable & Combustible Liquid codes is NFPA 30
- Durations and Densities is NFPA 16
- Aircraft Hangars is NFPA 409
- Firepumps: NFPA 20
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Water supply (Durations and Densities)
- Light Hazard: 100 GPM for 30 minutes
- Ordinary Hazard: 250 GPM for 60-90 minutes
- Extra Hazard: 500 GPM for 90-120 minutes
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Metric to Imperial conversions:
- Feet of pipe/3.28= meters
- Meters of pipe X 3.28= Feet
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Foam/water spray system
The smallest permissible Discharge orifice is:
¼”
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Airplane Hangar Doors
- Class 1: Over 28’
- Class 2: Less than 28’
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Dry System
Most common problem when water is coming out of the ball drip:
The clapper is not seated
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NFPA standard regarding Low, medium, and high Expansion Foam is:
NFPA 11
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Restrictions to type of piping and fittings used on a foam system:
Can't use galvanized pipe or fittings
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Extra Hazard (Group II)
Max time for water delivery in extra hazard (group II) is:
45 seconds
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Can a dry system be gridded?
No
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Minimum pipe schedule to be used for sway bracing?
Schedule 30
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Dry Chemical systems:
The expellant nozzle needs to be 20 pipe diameters away from the 90
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Foam systems:
Need to be pre-primed and flushed annually
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Filling a container with foam concentrate:
When filling a container with concentrate, pump it into the bottom of the container or use a long funnel so as not to aerate the foam
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Clean Agent:
Exposure Limits:
- 9% concentration: no longer than 5 minutes
- Greater than 11%: No longer than 1 minute
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Conversions:
- 1 cubic foot=6.24 Imperial Gallons or 7.5 US Gallons
- 1 foot of water exerts .433 PSI
- 1 cubic foot of air = 0.076 Lbs
- 1 metre (height) of water exerts 9.81 kpa
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Fire Pump testing
Under no flow:
- Electric: monthly for 10 minutes
- Diesel: weekly for 30 minutes
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Testing:
- Check valves: 5 years
- Main drain: annually
- Water flow alarms: quarterly
- F.D.C: Monthly
- Standard sprinklers: 50 years
- Quick Response: 20 years
- Dry Pendants: 20 years
- High Temperature Heads: 5 years
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Tube Bending (diameter of bend):
2” or smaller has a diameter of 6 pipe diameters 2 ½” or larger is 5 pipe diameters
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Flushing Requirements of Underground Piping:
- 4” 390 GPM
- 6” 880 GPM
- 8” 1560 GPM
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Limited Water Supply:
Pressure tank sizes:
- Light Hazard: capacity not less than 2,000 gallons
- Ordinary Hazard Group 1 & 2: capacity not less than 3,000 Gallons
- Smallest acceptable water supply considered by insurers advisory organization is 6,000 Gallons
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ABC method of testing a dry valve:
- Lock the clapper open
- Plug the autodrip
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Gravity Tanks:
- Min size of fill pipe: 2”
- Min size of overflow pipe: 3”
- Max time to fill tank: 8 hrs
- Min size of discharge pipe: 6”
- Location of a water level supervisory switch: 12” below High water level
- Min size of tank drain: 2”
- Min temp of water: 42 F
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Pressure Tanks:
- Needs to be replenished in 4 hours
- Fill 1/3 air, then 2/3 water
- Min pressure is 75 PSI
- Min size of water supply pipe: 1 ½”
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