Detection & Release Flashcards
2 kinds of valves for pre action and deluge are
Latch Clapper Valves
Differential Type Valves
Where is the chamber for a Latch Clapper valve
Isolated from the rest of the valve
Define how a latch clapper valve operates
When the isolated chamber receives water pressure, it acts on a lever to hold the valves clapper against supply
2 examples of latching pre action valves are
Reliable B & BX
Grinnell/Gem Multimatic Model A-4
What kind latching mechanism does a ASCOA model F pre action valve use
Diaphragm actuator
Differential Ratio for Pre-Action Valves is generally
2-3.2 to 1
The 3 most common actuation methods are
-Wet Pilot Lines
-Electrical Detectors
-Pressurized Air or Nitrogen Pilot lines
What is the most simple actuation method
Wet Pilot Line
If automatic sprinklers are used as detectors, how must they be installed
In accordance with their listing as sprinklers
When a sprinkler head has a different deflector and is designed to be used in a pilot line what are they called
Fixed Temperature Release Device
Some Fixed temperature release heads for pilot lines can go how far apart
40ft x 40ft
What limitations do wet Pilot lines have
-How high they can be above the valve
-Total length of pilot line piping that can be run without increasing size
(Manufacturer specifies exact amount)
When sprinklers are subject to freezing, what must pilot line contain
Pressurized air or nitrogen
The transition from water to air, in a pneumatic pilot line is made with
Dry-Pilot Actuator, installed on pilot line near valve
The pneumatic actuator is what kind of “valve”
Deferential valve
Model C rate of rise release will activate when
Temperature increase of 15F per minute
Model C Rate of rise release is also equipped with what, for smoldering fires
A fixed temperature detector as a safeguard
How many C1 Releases can be placed on a single line
No limit
How is the C1 Releases reset
Self Resetting
How does the C1 Release operate
The tube element expands faster the the rod element, causing a pulling force on the lever arm, then depresses Schrader valve, venting pressure
C1 release preset standard gap is
0.025”
C2 release pre set gap is
0.018” gap
What keeps a preaction/deluge valve open?
Pressure Operated Relief Valve (PORV)
The PORV will remain open until the pressure from the sprinkler system drops below
5psi
Maximum air pilot line length of piping is
1000ft of 1/2” pipe
Where is the pneumatic actuator installed with relation to PORV
Above PORV in releasing line
What system was the original rate of rise system
ASCOA
When do rate of rise fire detectors operate
When the rate of temperature increase exceeds what is expected to be normal
As a general rule of thumb, rate of rise systems are much more ______ then fixed temperature equipment
Sensitive
ASCOA rate of rise systems are based on what principle
Air expands when heated
(If the air is confined, the expansion will create pressure)
How does the ASCOA system work
Temp rises, which creates air pressure, this pressure goes through tubing to a diaphragm which sets levers in motion
HAD stands for
Heat Actuated Device
What is a HAD
-Detects fire heat and absorbs it, heats the air inside the tubing to create pressure
-Air tight, hollow chamber with no moving parts.
What are HADs generally made of
Brass
What air tubing is used with an ASCOA rate of rise system
1/8” copper tubing
What does the compensating device do with a ASCOA rate of rise system
-Allows pressure changes caused by normal temperature changes to bleed off or enter tubing.
-must be calibrated
What happens if an excessive number of HADs are connected to a single line of air tubing
Pressure developed by fire heat in HADs close to fire would be absorbed by the ones farther away from the fire
HADs in groups of limited numbers is commonly referred to as
Thermal systems or circuits
In a supervised Deluge system where explosions may rupture part of the HAD, what is required
System modification so the system will operate on total pressure loss as well as rate of rise (double acting release instead of standard)
HAD fusing elements temperature rating
Up to 360F
HADs have the same colour coding and operating temperatures as
Automatic sprinklers
What is the mercury check valve made of
Plastic with stainless steel fittings
How many “wells” does a mercury check valve have
2 wells
On mercury check valves, the side that is wide at the top and narrow at the bottom is the _____
Inlet
Mercury check valves measure the required pressure in
Inches of water Column
The ASCOA system will operate when the rate of temperature exceeds
15F in one minute
With the compensating vent on an ASCOA system, the finer vent makes detection _____ and when are they used
- More sensitive (higher # rating)
- used when temperature fluctuations are slow (non fire conditions)
With the compensating vent on an ASCOA system, the coarser vent makes detection _____
-Less sensitive ( lower # value)
-Used when temp. Fluctuations are faster (non fire conditions)
The adjustment of the release pressure setting on the ASCOA rate of rise system shall only be set
At the factory, must be specified when ordering
ASCOA recommends that mercury checks be used in
All installations
When a release is used with mercury check valves, what is the pressure setting and # of vent
-1/2”
-No. 40 vent
Without a mercury check valve, releases may be ordered with settings up too
4-1/2”
What determines the pressure setting in a mercury is check valve
The amount of mercury placed in each check valve (measured on manometre “U” tube)
The number of mercury checks connected to any rate of rise release or valve should generally not exceed
28 (to avoid too large of volume for the manifold)
ASCOA thermo-pneumatic system is subject to a pressure of
1-1/2” psi
When is a low pressure alarm
Given in the ASCOA thermo pneumatic system
1/2 psi
The air pressure pump in an ASCOA thermo pneumatic system will come on and shut off at what pressures
Starts at 1psi
Shuts off at 1 1/2psi
Air dryer for ASCO thermo pneumatic system system is filled with
Blue or mixed blue and white drying agent
How can you tell the drying agent must be replaced with ASCOA thermo pneumatic system
Blue material becomes pink or white (means it’s saturated with moisture)
What is used for testing and setting components of the ASCOA rate of rise system
Manometers
The 9” (small) manometer is used for measuring
Circuit mercury check
The 18” (large) manometer is used for
Airline mercury check
The scale used with a manometer is
Graduated in eighths of an inch, with 0 in the centre
When testing a manometer for air tightness, how is it verified
Water column must stay out of balance, if the water comes back level with eachother, atmospheric air has entered the manometer
The number rating on a manometer is what
The number of seconds required for a column of water in one leg of the U tube to travel one inch
Air line restrictor in current use is made of
Brass 2-1/2” end to end
1/4” male pipe threads at both ends
How do you determine the proper setting of air line restrictors
-Add the average settings of thermo vents x 3
-Divide this number by the number of thermo vents = # of restrictor
The Grinnell/gem rate of rise system was discontinued in
1988
What determines the sensitivity of the circuit in a Grinnell/gem rate of rise system
Mercury check valve
The Grinnell/Gem release and its circuits are pneumatically supervised at approximately
24 ounces per square inch
How does a Non interlock pre action system operate
Either System Sprinkler, or a detection system trips the valve.
How does a Single interlock system operate
-Operation of a detection device
(operation of system sprinkler will NOT activate the system)
How does a Double interlock pre action system operate
Operation of both sprinkler and detection system is required to trip the valve
(used extensively in freezers and ovens)
How is the Viking Firecycle system unique
Automatically turns itself off and back on as needed to control or extinguish a fire with minimal water discharge
In a single interlock pre action system, if the detection system malfunctions what will happen
Valve will trip, water will enter piping but not go anywhere since sprinkler hasn’t gone off
Single interlock systems are most commonly used where
-When dry pipe systems would exceeded the capacity normally permitted on a dry pipe valve
-where it is important to control accidental water discharge due to damaged sprinkler piping
The key to the Viking pneumatic double interlock system is
The pressure operated shut off assembly (POSO)
Main purpose of a non-interlock pre-action system is
To overcome the time delay inherent in a large dry system
What kind of system is the fire cycle system similar to?
Essentially, a more sophisticated type of single interlock electrically activated pre-action system
What makes the main Valve in a Viking fire cycle system unique
The addition of a spring in the priming chamber to assist in closing the clapper
The Viking fire cycle system must have backed up batteries in a battery charger, capable of how much power supply
90 hours emergency power supply
With the Viking fire cycle system, a detector has a telltale tab that will fall away at what temperature
800°F
The Viking fire cycle detector circuit timer goes for how long
One to five minutes
Linear type heat detector has been around how long
60 years
Where would protectowire primarily be used?
Refrigerated storage and aircraft hangers
What kind of system would protectowire generally be coupled with
Double interlock pre-action systems
Who installs protectowire
The sprinkler contractor and their journeyman
2 most common types of Linear type heat detectors are
-Analog (integrating) Linear Type
-Digital Linear type (protectowire)
How does protectowire work
The inner conductors are coated with a polymer that melts at a predetermined temperature which allows the conductors to make contact with one another and send an alarm condition
Protectowire Type EPC consist of
-Durable vinyl, outer jacket
-Use in both commercial industrial applications
-Low moisture absorption, resistance to chemicals, flexible @ low temperatures, flame retardant
Protectowire type EPN utilizes
-dual jacket with inner layer of vinyl and an outer film of weather resistant 612 nylon
-industrial use (conveyors)
-high abrasion resistance, resistant to salts, oils, petroleum products
Protectowire type EPR consists of
-Flame retardant polypropylene based jacket w/ UV stabilizer
-industrial applications
-Best for higher ambient temperatures
Protectowire is what kind of sensor
Fixed tempature
Protectowire must be installed how
In continuous runs without taps or branches
Protectowire “regular” temp
155F
Protectowire “Intermediate” temp
190F
Protectowire “High” temp
280F
Protectowire “Extra High” temp
356F
What is proximity or special application protection
Installation of the detector close to the hazard in order to provide a rapid response
Protectowire linear heat detector should be how far from the ceiling
20”
Where can Protectowire also be installed
Underside of solid joists or beams where the beams are less then 12” and less then 8ft on centre
How is spacing measured for protectowire
Horizontally
Who determines protectowire final location and spacing
Engineer
VESDA was developed when
Late 1970s
What is VESDA known for
Very early smoke detection
Which contractor generally does the VESDA system installs
Usually fire alarm contractor
How does VESDA system work
Drawing air back into a network of piping which is attached to a detector
(air goes through a multistage filter, then sent to laser detection chamber for smoke detection)
VESDA is how much more sensitive then a conventional smoke detector
1000x
4 stages of a fire are
- Incipient pre combustion stage
- Visible smoke
- Fast Flaming
- Intense Heat
VESDA is set up in 3 stages which are
- ALERT
- ACTION
- FIRE
If there’s a rapid smoke development within a VESDA system, what happens to the stages
Overridden, immediately goes to FIRE stage
VESDA used to be used exclusively in what industry
Telecommunications
VESDA is used in what systems
-FM 200
-Intergin FE-13
-Carbon Dioxide
-Pre Action
Explain piping for a VESDA system
Similar to sprinkler piping but it’s piping with small holes in it to sample air
Every VESDA system is capable of monitoring how big of an area
20,000sqft
2 types of mercury checks are
Air line mercury check
Circuit mercury check
(Both are Postive liquid check valves)
Where is the air line mercury check located
Air supply line, between air line restrictor and the release
Air line mercury check size
7” high by 2” wide
What is the air line mercury check designed to do
If flow is reversed, the pressure must exceed 3psi to over come the weight of the mercury
How is the air pressure setting determined with air line mercury checks
The depth the stainless steel tube projects into the pool of mercury
Air line mercury check is normally preset at what from the factory
1-1/2” of water column
Where are circuit mercury checks located
In air tight release enclosure
4 releasing devices for pre action are
Pilot lines
Pneumatic actuator
Electric solenoid
Emergency release
Max amount of time for air to replenish in a dry system
30 minutes
Max amount of time for air to replenish in a pre action/dry system in a refrigerated area
60 minutes
(5F, -15C)
When may relief valves be omitted for a single lock pre-action system
When the air supply is not capable of developing more than 15 psi
Max size of system, single interlock
1000 sprinklers
Max size of non-interlock system
1000 sprinklers
Max size of double interlock sprinkler system
500 gallons
Sprinkler pipe detection devices shall be supervised when
When more than 20 sprinklers are on the system
Minimum supervisory air pressure for non-interlock and single int air lock systems
7 psi
What pre-action systems cannot be gridded
Double interlock, any pre-action system protecting storage occupancies
What system is allowed to protect miscellaneous storage, but not shelf storage
Single interlock, non-interlock
What shall the slope be for sprinkler piping in a dry system
-Mains shall be pitched 1/4” per 10 feet
-branch lines shall be pitched 1/2” per 10 feet
All sprinkler piping in refrigerated areas shall be pitched how much
1/2” per 10ft
What is required in a wet system with over 50 gallons trapped
1” valve
What is required in a wet system with 5 to 50 gallons trapped
3/4” valve
What is required in a wet system under 5 gallons trapped?
1/2” nipple plug or cap
When in a refrigerator area, what is required for trap sections?
Drum drip assembly
Acceptance test for pre-action system consist of
-200 psi 2 hours no loss or
50 psi in excess of system pressure whichever is greater
What pre-action systems require a pneumatic acceptance test
Double interlock
What does a pneumatic acceptance test consist of?
40 psi 24 hours 1.5 psi loss
Double interlock system must have hydraulic and pneumatic acceptance test
What does an integrity test for a pre-action system consist of
-40 psi for 2 hours, 3 psi loss permitted
-System working pressure isolated for 4 hours in low pressure switch may not activate
Four basic components that must be present in a rate of rise system are
-HADS
-1/8” copper tube
-compensating vent
-release
What is the spacing for HADS?
15x15
PST must be supported every ___ ft
6ft
Vent used only on releases and only when mercury checks are used
40
Vent used in offices and where temp changes are slow
20
Vent used outdoors in areas where temp changes are moderate
10
Vent used in ovens and other areas were temp is rapidly changing
5
vent used in rare occasions were temp changes are extreme
4 to #1
2 types of diaphragms in release
Single action - will only operate when there is a sudden increase in pressure
Double action - will operate with a sudden increase or decrease of pressure
The pressure required to trip a release is measured in
Inches of water column
HADS are divided into groups of no more then
6 (called thermal system)
When using the small manometer, measurements exceeding how much should be avoided
3”
Blocks or banks of mercury checks can have how many connected
4
Max number of checks on a single rate of rise system should not exceed
28
Suprotex system is supervised with how much air pressure
1 1/2” psi
How many remote stations may be connected to one check
4-5
Detection tubing for ASCOA suprotex
1/8” with 0.08” ID
Grinnell Protomatic detection tubing
1/8” with 0.05” ID
What kind of compensating vent on ASCOA suprotex system
Fixed
Compensating Vent size on grinnell protomatic is _____
Adjustable
Air pump operates when with ASCOA suprotex system
Off: 24oz
On: 16oz
Air pump operates when for grinnell protomatic
Off: 24oz
On: 21 oz
Fixed temperature release device require testing after how long
20 years
Protectowire is installed with what NFPA
NFPA 72
What is the operating principle of the C1 & C2 release
Metals expanding at unequal rates
Where can the C1 be installed
Inside or outside but it is not intended for corrosive environments
What release must be used if sea water is present
C2 Release
Fixed temperature release on C1 &C2 from factory (temp rating)
155F
What size outlet on C1&C2
1/2”
Spacing for C1 Release
50x50
2500sqft
Ambient temperature range for C1 and C2 Release
-40F to 140F
(-40C to 60C)
C1 and C2 release rated working pressure
250psi
C1 and C2 release body k factor is
5.5
How far can C1 & C2 release be from walls and ceilings
-Minimum 4” from walls
-Minimum 4” from ceilings but cannot exceed max distance down of sprinkler heads
Indicator cap will blow open at what psi for C1 & C2 release
2psi
Air pressure for C1 and C2 release where supply is 175 psi and under
Air pressure at 30 psi
What is the air pressure for a C1 and C2 release where supply is 175 to 250 psi
50psi
What release is deigned for outdoors and corrosive areas
C2 Release
Max spacing for C2 release
40x40
1600sqft
What is required if C1 or C2 is in the sunlight
Weather hood
What is the piping that feeds the C1 and C2 release
1/2” Galv or copper
Trimpac Firecycle rated working pressure
250psi
Trimpac firecycle gauge pressure
0-300psi
What is the Viking firecycle multi cycle detector
Heat sensitive, normally closed, electrical detector, that operates at a fixed temperature
What “label” is on Viking firecycle multi cycle detector
300F label, if the label turns black the detector must be replaced
Viking fire cycle multi cycle detector minimum spacing
40x40
1600sqft
Viking firecycle multi-cycle detector distance from sprinklers
12-18”
Viking firecycle multi-cycle detector Minimum distance from wall
Must not exceed one half of maximum spacing
(No more then 20’ from wall)
What is the minimum number of detectors to be installed on a Viking fire lock multi cycle system?
2 detectors
What is smoke stratification?
Smoke Stratification occurs when the buoyancy force lose momentum before reaching a ceiling
How are flame detectors designed
To detect the absorption of light at specific wavelengths
(so they can differentiate between real and fake fires)
4 primary flame sensing technology used today are
-UV
-UV/IR
-MSIR
-Visual Flame Imaging
UV detector range
Up to 50ft
Multi-Spectrum IR flame detector range
Up to 200ft
Field of view for most flame detectors is
90° to 120°
VESDA is used in operating temperatures of
0F to 200F
Victaulic series 767 fire lock electric pneumatic actuator will activate when
Once pressure reaches 7psi
Max spacing for protectowire
50ft
The lever on the release of the suprotec is capable of producing how much weight
50lbs
Manometer measurement
Inches of water column
HADS divided into groups of no more than ____ per mercury check valve
6
Airline mercury check plastic is what kind
Lucite
For remote actuation, if longer runs of more then _____ is required, a booster may be needed
400ft
Supervisory air in a double interlock
15psi
Back setting is the pressure required for air to flow in the opposite direction and is what pressure
5 - 1/2” of water column
Type TRI protectowire is unique how
Dual temperature detector which is capable of initiating separate pre alarm and alarm signals
What is the maximum length protectowire can be run for a single zone
6500ft
