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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. - correct 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 ______ - correct answer As close to the property where the sprinkler system is being installed. (Ref, NFPA 13 Sec. A.24.2.2. or NFPA 291) What formula is used to determine the discharge coefficiant relating pressure and flow rate? - correct answer K = Q / (Square root of P) What best describes a tree system? - correct 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: - correct 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? - correct answer NFPA 13 & 24 (Both in Chapter 10) Which of the following should you inspect on an extension cord before each use? - correct answer The grounding prong & the insulation for nicks, cuts, or damage ________ indicates a mandatory req. according to NFPA definitions. - correct 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? - correct 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): P friction loss = 4.52 x Q 1. c 1.85 x d 4. P friction loss = 4.52 x 100 1.
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. - correct 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 √ 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. - correct 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? - correct 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: - correct 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? - correct 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? - correct answer 10 ft. Reference NFPA 13 2016, Section 9.1.5.2.2 - when 2 in. screws cannot be used, 1 ¾ in. screws can be used if the maximum hanger spacing in 10 ft. The owners info cert. indicates the property to be protected will contain nitrate film. Which of the following is also req. to be provided? - correct answer Type, arrangement, location, and intended maximum quantities. Reference NFPA 13 2016, Figure A.23.1(b).
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. - correct 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) - correct 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? - correct 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? - correct 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. - correct 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 - correct answer 15ft Ref. NFPA 13 2016 Table 8.6.2.2.1. Ordinary Hazard is a term the specifies: - correct 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. A system that provides 1 1/2 inch hose stations to supply water for use primarily by trained personnel or by the fire department during initial response is a ___________. - correct answer Class II Standpipe REfrence NFPA 14 2016 Section 3.3.19.2. Which of the following statements is incorrect when describing a deluge system? - correct answer Deluge system detection devices should be automatically supervised. Deluge systems are required to be automatically supervised. Reference NFPA 13 2016, Sections 3.4.4, 7.3.3.1 and 7.3.3.2. Choose all that apply to a Dry Pipe System - correct answer 1. Require approved pressure gauges on the water side of the dry pipe valve.
- Permit Horizontal sidewall sprinklers to be installed so that water is not trapped.
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. - correct 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: - correct 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. - correct 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?
- correct 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? - correct 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 Q 3 = 29.84 x 0.7 x (2.5) 2 x √12 = 452.09 gpm Q total = Q 1 + Q 2 + Q 3 Q total = 452.99 gpm + 452.99 gpm + 452.99 gpm = 1356.27 gpm Round down to 1356 gpm In a water flow test using two hydrants, _________ pressure is the pressure at the hydrant where the water is not flowing. - correct answer Residual Pressure Refrence NFPA 13 2016 Section A.24.2.2. What type of information is collected when you are conducting a water flow test from one hydrant? - correct answer Static and Residual Pressure Refrence NFPA 13 2016
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 - correct 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? - correct 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? - correct 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? - correct answer Step #1: 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): 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 1.61 4. P friction loss = 0.317 psi/ft Step #2: Determine the total friction loss for 100 gpm flowing through 100 ft. of 1 ¼ in. Schedule 40 black steel pipe: 100 ft. x 0.672 psi/ft = 67.2 psi Step #3: Determine the pipe length to produce the same friction loss in the 1 ½ in. pipe: y ft. x 0.317 psi/ft = 67.2 psi y = 67.2 ÷ 0.
The size requirements for the suction and discharge pipe of a fire pump with a rating of 1000 gpm are: - correct 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? - correct 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? - correct 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? - correct 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. - correct 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 ____% - correct answer 150, 65,140. Reference NFPA 20 2016, Section 6.2.
