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NICET LEVEL 1 - WATER BASED
LAYOUT
Toggle hangers shall be permitted only for the support of pipe __________ inches or smaller in size under ceilings of hollow tile or metal lath and plaster. - ANSWER-1 2/2 in. (ref. NFPA 13 2016 Sec. 9.2.1.1.2. While conducting a flow test, the chosen hydrant should be ______ - ANSWER-As close to the property where the sprinkler system is being installed. (Ref, NFPA 13 Sec. A.24.2.2. or NFPA
What formula is used to determine the discharge coefficiant relating pressure and flow rate? - ANSWER-K = Q / (Square root of P) What best describes a tree system? - ANSWER-Cross mains and the branch lines are not tied together, providing only one path of water flow. Factors that define Occupancy Group Hazard 2 include: - ANSWER-Quantity and combustibility of contents are moderate to high. Stockpiles of contents with moderate rates of heat release do not exceed 12 ft and stockpiles with high heat release do not exceed 8 ft (Ref NFPA 13 Sec. 5.3.2)
Which of the following standards contain reqs. pertaining to the installation of underground piping? - ANSWER-NFPA 13 & 24 (Both in Chapter 10) Which of the following should you inspect on an extension cord before each use? - ANSWER-The grounding prong & the insulation for nicks, cuts, or damage ________ indicates a mandatory req. according to NFPA definitions. - ANSWER-Shall. (Ref. NFPA 13 2016, Sec. 3.2.4.) 100 GPM is flowing through 100' of 1 1/4 in. Sch. 40 pipe. How many feet of 1 1/2 in. pipe will produce the same friction loss? - ANSWER-Assume this is Schedule 40 pipe, C = 120. Use the Hazen-Williams formula to calculate the friction loss for the 1 ¼ in. pipe and the 1 ½ in. pipe. For 1 ¼ in. pipe (ID = 1.38): P friction loss = 4.52 x Q 1. c 1.85 x d 4. P friction loss = 4.52 x 100 1. 120 1.85 x 1.38 4. P friction loss = 0.672 psi/ft For 1 ½ in. pipe (ID = 1.61):
Define both the constant, y, and the exponent ,z, for q in the Hazen-Williams friction loss formula shown Below: P = L x (y x Q^z) (c^1.85 x d^4.87) - ANSWER-4.52, 1.85. Reference NFPA 13 2016 Section 23.4.2.1.1. A water flow test was conducted using 1 hydrant, flowing with two 2 1/2 inch outlets. Which is the approximate water flow rate, if the pitot reading was 15 psi. The hydrant outlet coefficiant is 0.8. - ANSWER-The correct ANSWER is 1156 gpm. Solution #12: Q 1 = 29.84 cd 2 √ P Q 1 = 29.84 x 0.8 x (2.5) 2 x √ 15 Q 1 = 577.8 gpm Both outlets are 2 ½ in., with the same outlet coefficient. Therefore, Q 1 = Q 2 The total flow rate is then: Q 1 + Q 2 = Q total Q total = 577.85 gpm + 577.85 gpm = 1155.70 gpm, round up to 1156 gpm
If a cross main in a ________ pipe sprinkler system has three branch lines per bay, one intermediate hanger shall be permitted to be omitted, if a branch line hanger is installed on the starter peice. - ANSWER-Steel. Reference NFPA 13 2016, Section 9.2.4.3. NFPA 13 specifies the depth of cover fro underground pipe of a minimum of 2 1/2 ft, 3 ft. under driveways and 4 ft. under railroads tracks. However, it must be at least 1ft. below the frost line. If the frost line is 2 1/2 ft, what is the minimum depth of cover under a driveway? - ANSWER-3 ½ ft. Reference NFPA 13 2016, Section 10.4. If you are laying pipes under driveways, you must go down a minimum of 3 ft. However, you must be at least 1 ft. below the frost line. In this case that is 3 ½ ft. Ordinary Hazard is a term that specifies: - ANSWER-An occupancy classification, More combustibility than light hazard, and A system area limitation of 52,000 ft 2. Reference NFPA 13 2016, Sections 5.3 and 8.2.1. What type of temperature is required for a sprinkler installed 2ft above a heating duct? - ANSWER-Intermediate. Reference NFPA 13 2016, Table 8.3.2.5(a). A three screw ceiling flange is used to attach the hangers for 6 in. Sch. 40 pipe. If 1 3/4" lag screws are used, what is the maximum spacing for the hangers? - ANSWER-10 ft.
Copper tube that has the greatest (largest0 inside diameter for 1 inch. nominal tube is: - ANSWER-Type M. Reference NFPA 13 2016, Table A.6.3.5. Calculate the equivalent length of 4 in. Schedule 40 Black steel pipe of a 90 degree long turn elbow - ANSWER-6 ft. Per NFPA 13 2016, Table 23.4.3.1.1, we find the equivalent length for a 4 in. Schedule 40 Black steel pipe with a 90 0 long- turn elbow is 6 ft. Determine the maximum spacing permitted for an Extra Hazard hydraulically calculated system with a density less than 0. gpm/ft^2 - ANSWER-15 ft. Reference NFPA 13 2016, Table 8.6.2.2.1(c) In water flow test using two hydrants, ______ pressure is the pressure at the hydrant where the water is not flowing. - ANSWER-Residual pressure. Reference NFPA 13 2016, Section A.24.2.2. NFPA 13 permits branchline hangers to be attached to metal roof decks if the pipe size doesnt exceed ____ inch(es) - ANSWER-1 in. Reference NFPA 13 2016, Section 9.2.1.4.1. How more water can a (17/32) sprinkler deliver than a (1/2) sprinkler? - ANSWER-Solution #7: k ½ = 5.
k 17/32 = 8 Percentage increase: 8 - 5.6 = 43%
Which of the following reqs. pertaining to the relief valve for a centrifugal pump is incorrect? - ANSWER-The relief valve shall only be hydraulically sized. Ref. NFPA 20 2016 Sec. 4.19.2.1. Where the suction supply is under sufficient pressure to be of material value without the pump, the pump shall be installed with a __________, which shall be at least as large as the pipe size required for the discharge pipe. - ANSWER-Bypass Valve Refrence NFPA 20 2016 Section 4.15.4. Determine the maximum spacing permitted for an Extra Hazard hydraulically calculated system system with a density less than 0.25 gpm/ft^2 - ANSWER-15ft Ref. NFPA 13 2016 Table 8.6.2.2.1. Ordinary Hazard is a term the specifies: - ANSWER-An occupancy classification, More combustibility than light hazard, and A system area limitation of 52,000 ft 2. Reference NFPA 13 2016, Sections 5.3 and 8.2.1.
Refrence 13 2016 Section 3.6.4.2. A standpipe system with no permanently attached water supply that relies exclusively on the fire department connection to supply the system demand. - ANSWER-Manual Dry Reference NFPA 14 2016 Section 3.3.17.4. For corrosive water conditions, steel pipe on the suction side of the pump is required to be: - ANSWER-Galvanized or painted on the interior with a paint recommended for submerged surfaces Refrence NFPA 20 2016 Section 4.14.1.2. The distance between the bottom of the strainer and the bottom of the wet pit on a vertical shaft turbine pump should be: - ANSWER-One half of the pump bowl diameter but not less than 12 inches. Reference NFPA 20 2016, Figure A.7.2.2.1 (see note in figure) Determine the max allowable shutoff pressure for a fire pump with a rated cpacity of 750 gpm and a rated head of 60 ft. - ANSWER-36 psi. 1.4 x 60 ft = 84 ft, Head = P psi/0.433, P = Head x 0.433, P = 84 x 0.433 = 36.37 psi.
This complex phenomenon specific to pumps or other hydraulic equipment is the result of suction pressure falling below vapor pressure corresponding to the water temperature: - ANSWER- Cavitation A high-rise building where the floor of an occupiable story is greater than _____ above the lowest level of fire department vehicle access. - ANSWER-75ft Refrence NFPA 14 2016 Section 3.3.7. In a manufacturing plant classified as Ordinary Hazard Group 2, the sprinkler system is provided with one inside hose station. Per NFPA 13 2016, Table 11.2.3.1.2. what is the minimum inside hose demand? - ANSWER-50 gpm A water flow test was conducted using 2 hydrants. Both 2 1/2" outlets were used on hydrant #1 while one outlet was used on hydrant #2. The pitot reading at each hydrant was 12 psi. If the discharge coefficient is 0.7, what is the total water flow (gpm) during this test? - ANSWER-The correct ANSWER is 1356 gpm. Solution #14: Q = 29.84 cd 2 √P Q 1 = 29.84 x 0.7 x (2.5) 2 x √ 12 = 452.09 gpm Q 2 = 29.84 x 0.7 x (2.5) 2 x √ 12 = 452.09 gpm
Reference NFPA 13 2016, Section 23.1.3(35). NFPA 13 defines the information which should be included in the working plans to be submitted to the AHJ for approval. These include which of the following: - ANSWER-Location, Occupancy Classification, Location of concealed spaces, Area protected by each sprinkler, Number of sprinklers. Reference NFPA 13 2016, Section 23.1.3. Who must sign the Owner's Certificate? - ANSWER-The owner or the owner's representative. Reference NFPA 13 2016, Figure A.23.1(b). The Owner's Certificate declares the intended use of the occupancy to be protected. Water flow test info should be included on what set of plans? - ANSWER-The drawings that accompany the Owner's Information Certificate. Reference NFPA 13 2016, Section A.23.1. The Owner's Information Certificate indicates the property to be protected will contain nitrate film. Which of the following is also required to be pro - ANSWER-Type, arrangement, location, and intended maximum quantities. Reference NFPA 13 2016, Figure A.23.1(b). What is defined as measuring 12 inches or more in its least dimension in any floor, platform, pavement, or yard? - ANSWER-A floor opening. It is an opening through which persons may fall.
Reference OSHA 29 CFR, Part 1910.21(a) (2). _________ indicates a mandatory requirement according to NFPA definitions? - ANSWER-Shall. Reference NFPA 13 2016, Section 3.2.4. 100 gpm is flowing through 100' of 1 1/4in Schedule 40 pipe. How many feet of 1 1/2in pipe will produce the same friction loss? - ANSWER-Step #1: Assume this is Schedule 40 pipe, C =
- Use the Hazen-Williams formula to calculate the friction loss for the 1 ¼ in. pipe and the 1 ½ in. pipe. For 1 ¼ in. pipe (ID = 1.38): P friction loss = 4.52 x Q 1. c 1.85 x d 4. P friction loss = 4.52 x 100 1. 120 1.85 x 1.38 4. P friction loss = 0.672 psi/ft For 1 ½ in. pipe (ID = 1.61): P friction loss = 4.52 x Q 1. c 1.85 x d 4. P friction loss = 4.52 x 100 1.
Step #2 : Using the information from the problem, determine velocity pressure: Q = 25 gpm, d = 2.245 in. P v = 0.001123x (25) 2 (2.245) 4 P v = 0.001123 x 625
P v = 0.028 psi The max allowable shutoff head for a pump with a rated capacity of 900 gpm and a rated head of 250ft is: - ANSWER- 350 ft. Max = 140% of rated head = 1.4 x 250 = 350 ft. The size requirements for the suction and discharge pipe of a fire pump with a rating of 1000 gpm are: - ANSWER-8 inches and 6 inches. Reference NFPA 20 2016, Table 4.27(a). A sprinkler system that is composed of 2 1/2" sch 40 steel pipe. What is the max distance between hangers? - ANSWER-15 ft. Reference NFPA 13 2016, Table 9.2.2.1(a) An installation req a 3 in sch 40 pipe. If a bend is req, what is the min. bending radius? - ANSWER-The correct ANSWER is 15 in. radius. Reference NFPA 13 2016, Section 6.3.8. Since the diameter is over 2 ½ in, we can have a minimum radius of 5 times the pipe diameter. This is 5x3 in.=15 in.
What is the minimum operating pressure for any sprinkler? - ANSWER-The correct ANSWER is 7 psi. Reference NFPA 13 2016, Section 23.4.4.11.1. Determine the maximum operating pressure for an Extra Hazard Group 2 sprinkler. - ANSWER-The correct ANSWER is 175 psi. Reference NFPA 13 2016, Section 23.4.4.12. The maximum operating pressure for an Extra Hazard sprinkler is 175 psi. Centrifugal pumps shall furnish not less than ____% - ANSWER- 150, 65,140. Reference NFPA 20 2016, Section 6.2.
