Intro to Automatic Sprinklers Ch 1-2 Flashcards
What is the ignition temperature of normal combustable materials?
300-1,000 degrees F
What are the 4 ways to extinguish a fire?
- remove heat (cooling)
- remove fuel
- remove oxygen
- Stop the reaction
What gas can be used to extinguish fire and how does it extinguish it?
carbon dioxide - it’s heavier than air so it prevents oxygen from getting to the fire - it smothers it
What 2 ways does foam extinguish a fire?
primarily smothering, also cooling
t/f
water extinguishes primarily by cooling
t
secondary: smothering
t/f
carbon dioxide extinguishes a fire primarily by inhibiting the chemical chain reaction
f
it smothers it
t/f
Halon extinguishes fire primarily by cooling
f
it breaks the chemical reaction
t/f
Dry chemical extinguishes fire primarily by smothering
f
it inhibits the chemical chain reaction
t/f
For most substances combustion occurs after the fuel has been vaporized
T
Describe a perforated pipe system and it’s drawbacks
Perforated pipes were attached to the ceiling, and each section was fed by a riser and controlled by a gate valve located outside a room or building.
Problems: poor distribution, openings subject to clogging…rust and foreign materials, heavy water damage
How was water supplied for the early automatic sprinklers?
elevated tank
Who first used the principle of a deflector?
Charles E. Buell
Who created the first practical application of automatic sprinkler systems?
Henry Parmelee (and his piano factory)
Who is credited with the rapid commercial development of the automatic sprinkler?
Frederick Grinnell
Who invented the first automatic sprinkler?
Major Harrison
“Old-type” sprinklers were invented when, and what made them different from the previous sprinkler heads?
1921; they used a bulb instead of the metal strut and fusible solder.
When did the “standard sprinkler” get it’s name, and what made it better than the old-type?
1958; radically changed pattern of water discharge
t/f
The metals used in a 212 degree F solder link all individually nave a melting point greater than 212 degrees F
T
t/f
The residential sprinkler operates faster than standard response sprinkler.
T
t/f
For many years sprinklers were primarily property protection devices
T
t/f
a single water system may supply a number of sprinkler systems
T
Define ADD
Actual Delivered Density (the amount of water actually delivered to extinguish the fire)
Define RDD
Required Delivered Density (the amount of water needed to extinguish the fire)
t/f
sprinklers around escalator openings are spaced closer than sprinklers in the remainder of the occupancy
T
Nfpa 13
9.3.5.1
t/f
The speed of operation of sprinklers is related to the height of the sprinklers above the fuel
T
t/f
It is an accepted rule of sprinkler protection that the higher the discharge pressure from the sprinklers the better the fire protection that is obtained
F
too much pressure = mist
t/f
Sprinkler systems in areas subject to earthquakes must be provided with flexible couplings
T
NFPA 13
18.2.1
List examples of light hazard occupancies
apartments, churches, schools, office buildings, hotels, public buildings, dwellings
what types of buildings fall in the ordinary hazard class?
ordinary mercantile, manufacturing, and industrial properties
List examples of ordinary hazard group 1 buildings
(low combustibility, stockpiles are less than 8 feet)
canneries, laundries, electronic plants
List examples of ordinary hazard group 2 buildings
(quantity and combustibility is moderate to high, stockpiles less than 12 feet)
cereal mills, textile plants, printing plants
What things classify a high hazard class group 1 occupancy?
severe fire variables that don’t usually involve flammable and combustable liquids
t/f
Pipe sizing is affected by the occupancy classification
T
NFPA 13
FIG 19.3.3.1.1
