CSLB C-16 Fire Protection (Trade Exam) — All Questions

Which description matches the Board's C-16 classification?

• a.Designs fire protection systems as a licensed engineer
• b.Installs electrical alarm and detection systems
• c.Services and refills portable extinguishers on a route
• d.Lays out, fabricates and installs fire protection systems✓

The classification covers laying out, fabricating and installing all types of fire protection systems and their associated equipment. Installing electrical alarm and detection systems is the work the definition expressly excludes. Servicing and refilling portable extinguishers on a route is a service activity, not the laying out and installing the definition describes. Designing systems as a licensed engineer is a separate professional license, not a contractor classification.CSLB C-16 classification text

Which work does the C-16 definition expressly leave out?

• a.Fire pump installation
• b.Sprinkler pipe fabrication
• c.Electrical alarm systems✓
• d.Underground fire main layout

The definition excludes electrical alarm systems. Fabricating sprinkler pipe, installing a fire pump and laying out underground mains all fall within the fire protection systems and equipment the license covers.CSLB C-16 classification text

Where does the Board place the former D-13 Fire Extinguisher Systems specialty?

• a.Under the C-10 Electrical classification
• b.Under the B General Building classification
• c.Under the C-61 Limited Specialty, unchanged
• d.Under the C-16 classification✓

The Board's limited specialty page lists D-13 as now under C-16. Electrical work and general building are different classifications, and C-61 no longer carries it as its own subcategory.CSLB C-61 Limited Specialty page

In which part of Title 24 is the California Fire Code published?

• a.Part 12
• b.Part 9✓
• c.Part 2
• d.Part 5

The California Fire Code is Title 24, Part 9. Part 2 is the California Building Code, Part 5 is the plumbing code and Part 12 holds referenced standards.2025 California Fire Code, Title 24 Part 9

When did the 2025 California Building Standards Code take effect?

• a.January 1, 2027
• b.January 1, 2026✓
• c.July 1, 2025
• d.January 1, 2025

The 2025 code cycle took effect on January 1, 2026, so the edition year does not set the effective date. January 1, 2025 is the start of the edition year, not the date the code took effect. July 1, 2025 is a mid-year date that is not the cycle's effective date. January 1, 2027 is a year later than the real date.California Building Standards Commission, 2025 codes

Which edition of NFPA 13 does the Board's current C-16 reference list name?

• a.2022
• b.2019
• c.2016
• d.2025✓

The March 2026 guide lists NFPA 13 (2025). The 2022 edition is the one in the earlier edition of the guide, and the 2019 and 2016 editions appear only in older local checklists.CSLB C-16 study guide 13E-16 (03-2026)

Which of these sprinkler standards is written specifically for one- and two-family dwellings and townhouses?

• a.NFPA 14
• b.NFPA 20
• c.NFPA 13D✓
• d.NFPA 13R

NFPA 13D is the dwelling-scale standard the fire code permits for one- and two-family dwellings, certain R-4 occupancies and townhouses, so it is the one written specifically for them. NFPA 13R covers Group R buildings of up to four stories within the height limits, so it is not written only for dwellings. NFPA 14 is for standpipes and NFPA 20 is for fire pumps.2025 CFC 903.3.1.3

A Group R-2 building has its roof assembly 48 feet above the lowest level of fire department vehicle access. Which statement is correct?

• a.NFPA 13R is not available because the roof is not under 45 feet✓
• b.NFPA 13R is available because the building has few stories
• c.No sprinkler standard applies since the building is residential
• d.NFPA 13D is available because the units are dwellings

For Group R-2 the NFPA 13R option requires the roof assembly to be less than 45 feet above fire department vehicle access, so at 48 feet 13R is not available and the building is sprinklered to NFPA 13. A low story count does not qualify it, because the height limit applies as well. Residential buildings are not exempt, since Group R occupancies are covered by the sprinkler requirements. NFPA 13D is limited to one- and two-family dwellings and townhouses, so dwelling units in an apartment building do not make it available.2025 CFC 903.3.1.2

How many sprinklers may a limited-area system have in a single fire area?

• a.No set maximum is stated in the code
• b.Six at most✓
• c.Twelve at most
• d.Twenty at most

The fire code caps a limited-area sprinkler system at six sprinklers in a single fire area. Twelve and twenty are not the cap, and the limit is not left open.2025 CFC 903.3.8.1

Which hazard classes may be protected by a limited-area system?

• a.Ordinary Hazard Group 2 and Extra Hazard Group 1
• b.A class chosen by the owner
• c.Light Hazard and Extra Hazard Group 1
• d.Light Hazard and Ordinary Hazard Group 1✓

Only areas classified as Light Hazard or Ordinary Hazard Group 1 qualify. Extra Hazard, Ordinary Group 2 and owner preference are not covered by the allowance.2025 CFC 903.3.8.2

A mechanical room is damp and contains electrical equipment. May the designer leave it unsprinklered for those reasons alone?

• a.No, those reasons alone do not justify omitting heads✓
• b.Yes, because the code exempts damp rooms from sprinklers
• c.Yes, whenever the room has a fire-rated door
• d.Yes, because electrical rooms are exempt

The fire code says sprinklers shall not be omitted merely because a room is damp, rated or contains electrical equipment. A rated door does not create an exemption either.2025 CFC 903.3.1.1.1

A vending display has a solid canopy 5 feet wide. What does the fire code require?

• a.No sprinklers, because the overhead heads already cover the display below
• b.Sprinklers in or under it, because it exceeds 4 feet in width✓
• c.Sprinklers at the front edge of the canopy
• d.Sprinklers if the canopy is over 8 feet wide

Section 903.3.3 requires sprinklers in or under covered kiosks, displays and equipment that exceed 4 feet in width, so a 5-foot canopy needs them. Overhead ceiling sprinklers cannot be relied on, because a solid canopy blocks their discharge. A sprinkler at the front edge only is not an arrangement the rule describes. The threshold is 4 feet, so an 8-foot trigger would leave a 5-foot canopy unprotected.2025 CFC 903.3.3

What minimum clearance does the fire code keep between sprinklers and the top of piles of combustible fibers?

• a.18 inches
• b.3 feet✓
• c.1 foot
• d.6 feet

The fire code maintains not less than a 3-foot clearance between automatic sprinklers and the top of piles of combustible fibers. One foot and 18 inches are too close and 6 feet is not the figure.2025 CFC 903.3.3

In which areas does the fire code call for quick-response or residential sprinklers?

• a.Commercial kitchens with hood systems and grease ducts
• b.Dwelling units and sleeping units in Group I-1 and R✓
• c.Parking garages of larger sizes
• d.Warehouses with high-piled storage areas

Section 903.3.2 lists dwelling units and sleeping units in Group I-1 and R, and light-hazard occupancies, among other places. High-piled storage, garages and kitchens are not in that list.2025 CFC 903.3.2

A K = 5.6 sprinkler operates at 49 psi. About how much does it discharge?

• a.39.2 gpm✓
• b.28 gpm
• c.8.75 gpm
• d.274 gpm

Q = 5.6 × √49 = 5.6 × 7 = 39.2 gpm. Multiplying K by pressure gives 274, dividing K by the pressure gives 0.11 rather than 8.75, and 28 gpm is the flow at 25 psi.Manufacturer data sheet (K-factor definition)

A K = 8.0 sprinkler must flow 48 gpm. What pressure is needed?

• a.384 psi
• b.6 psi
• c.48 psi
• d.36 psi✓

P = (48 ÷ 8.0)² = 6² = 36 psi. Six is the ratio without squaring, 384 multiplies K by flow, and 48 psi simply repeats the flow number.Manufacturer data sheet (K-factor definition)

A design shows a K = 5.6 standard sprinkler needing only 11.2 gpm, which calculates to 4 psi. What does the data sheet's minimum operating pressure of 7 psi mean for the design?

• a.The 7 psi applies to dry systems
• b.Pressure at that sprinkler must be at least 7 psi✓
• c.The 4 psi calculation stands because flow is met
• d.The sprinkler must be changed to a smaller K-factor

The data sheet's 7 psi minimum operating pressure is a floor at the sprinkler, so the design must deliver at least 7 psi there even though the formula gives 4 psi for 11.2 gpm. Letting the 4 psi calculation stand ignores that floor. Limiting the minimum to dry systems has no basis, because it is a property of the sprinkler itself. Switching to a smaller K-factor is not what the limit says, and at the same flow it would need more pressure, not less.Manufacturer data sheet (minimum operating pressure)

Which bulb color marks a 200 F sprinkler on a manufacturer's temperature table?

• a.Blue
• b.Green✓
• c.Black
• d.Orange

The table pairs 200 F with a green bulb. Blue marks the 286 F rating, orange marks 135 F, and black is used only for the high-temperature sprinklers rated 400 F and above. The table's other colors are red for 155 F and yellow for 175 F.Manufacturer data sheet (temperature ratings)

What maximum ambient temperature does the manufacturer's table pair with a 286 F blue-bulb sprinkler?

• a.300 F
• b.150 F
• c.225 F✓
• d.100 F

The table pairs 286 F with a 225 F maximum ambient temperature, while 135 F and 155 F go with 100 F and 175 F and 200 F with 150 F. The 300 F figure is above the rating itself.Manufacturer data sheet (temperature ratings)

A ceiling will reach 95 F at its hottest. Which is the lowest rating whose table maximum ambient temperature covers it?

• a.175 F
• b.155 F
• c.135 F✓
• d.200 F

A 135 F sprinkler is rated for ambient temperatures up to 100 F, so it covers a 95 F ceiling and is the lowest rating. The 155, 175 and 200 F ratings also cover it but are higher than needed.Manufacturer data sheet (temperature ratings)

What does a manufacturer say about the water distribution of a conventional sprinkler?

• a.The water goes toward the walls
• b.Half goes to the ceiling and half to the floor
• c.40 or 60 percent goes downward, the rest upward✓
• d.The water goes straight down

A conventional sprinkler sends 40 or 60 percent of the water downward and the rest upward, and the manufacturer warns not to use it in place of a standard spray sprinkler. Throwing water toward the walls is the job of a sidewall sprinkler. An even half to the ceiling and half to the floor is not the stated split. Sending all the water straight down describes none of the sprinkler's patterns, because the deflector gives a spherical pattern.Manufacturer data sheet (conventional sprinkler)

What liquid color does a manufacturer's high-temperature sprinkler table show for ratings from 400 F to 650 F?

• a.Orange
• b.Black✓
• c.Green
• d.Yellow

The high-temperature table lists 400 F, 500 F and 650 F ratings with black bulb liquid. Orange, green and yellow belong to the lower ordinary and intermediate ratings.Manufacturer data sheet (high temperature sprinklers)

A flow test reports three numbers. Which set is it?

• a.Static pressure, residual pressure and flow✓
• b.Residual pressure, pipe diameter and friction
• c.Peak pressure, average pressure and velocity
• d.Static pressure, pump pressure and elevation

A flow test yields the static pressure with no flow, the residual pressure while water flows, and the flow itself. Pipe diameter and friction are calculation inputs, not readings from the test. Peak pressure, average pressure and velocity are not recorded by a hydrant flow test. Pump pressure belongs to a fire pump test and elevation is a survey item, so neither is a result of the flow test.Moreno Valley Fire Department, Underground Fire Service Mains

Who must be notified before a water supply test is run, under the fire code?

• a.The sprinkler manufacturer
• b.The fire code official✓
• c.The building's insurance carrier
• d.The state water board

The fire code official is notified before the water supply test and may witness it or accept approved documentation afterward. The sprinkler manufacturer supplies equipment, not water, so it has no role in the test. The insurance carrier may want the results but is not the party the code names. The state water board does not oversee a local flow test.2025 CFC 507.4

One city's guideline allows a water supply test to be how old at plan submittal?

• a.No more than 24 months
• b.No more than 6 months✓
• c.No more than 12 months
• d.A test taken years earlier, if the pressure is high

The guideline says water supply testing and documents are no more than 6 months old at submittal. Twelve and 24 months are too long and age cannot be waived by high pressure.Moreno Valley Fire Department guideline

A city allows no more than 90% of the available supply to be used. If 80 psi is available at the design flow, what is the highest pressure the design may use?

• a.8 psi
• b.79 psi
• c.72 psi✓
• d.88.9 psi

Ninety percent of 80 is 72 psi. Dividing by 0.9 gives 88.9, which exceeds the supply, 8 psi is the 10 percent margin itself, and 79 has no basis.Moreno Valley Fire Department guideline

An owner's design standard tells designers to assume a 10 psi safety margin on hydrant and pump flow test results. Why?

• a.To compensate for the weight of the pipe
• b.To account for the sprinkler wrench torque
• c.To cover the cost of the building permit
• d.To allow for loss of static and residual pressure✓

The standard assumes a 10 psi margin to allow for deterioration in static and residual pressures from the tests. Pipe weight, torque and permit cost are unrelated to supply pressure.Harvard Medical School Facilities Design Standard, Division 21

Which Hazen-Williams C-factor does a hydraulics reference list for steel pipe in a wet system?

• a.140
• b.100
• c.120✓
• d.150

The reference lists 120 for steel in wet and deluge systems and 100 for steel in dry and preaction systems. The value 150 is for copper and plastic in wet systems, and 140 is not listed.Building Code Resource Library, Hazen-Williams formula

In the Hazen-Williams formula, what are the units of the P that is calculated?

• a.Psi at the sprinkler
• b.Gpm per square foot
• c.Psi per foot of pipe✓
• d.Feet of head per psi

In the Hazen-Williams formula P is the pressure loss in psi per foot of pipe. Psi at the sprinkler is the P of the sprinkler flow equation Q = K times the square root of P, not the friction formula's output. Gpm per square foot is a design density, not a pressure loss. Feet of head per psi is a conversion factor, not what the formula calculates.Building Code Resource Library, Hazen-Williams formula

What does the federal criteria document say about threading steel pipe thinner than Schedule 40?

• a.It may be threaded if hand-tightened
• b.It must not be threaded✓
• c.It may be threaded in dry systems
• d.It may be threaded with taper dies

Steel piping with wall thickness less than Schedule 40 must not be threaded, so Schedule 10 is joined by grooved couplings or plain-end fittings. Hand-tightening does not restore the wall cut away by the threads. Using it in dry systems is no exception, because the rule does not depend on system type. Taper dies still cut the thin wall, so they do not make threading allowable.UFC 3-600-01 section 9-7 (piping)

What minimum schedule does one owner's published criteria give for sprinkler piping 2 inches and smaller?

• a.Schedule 10
• b.Schedule 80
• c.Schedule 5
• d.Schedule 40✓

The criteria call for minimum Schedule 40 for piping 2 inches and less and minimum Schedule 10 for larger piping. Schedule 80 is heavier than required and Schedule 5 is thinner than the minimum.UFC 3-600-01 section 9-7 (piping)

What plastic underground pipe does a Sacramento fire district standard approve for private service mains?

• a.PVC C900, Class 150 or greater✓
• b.CPVC pipe of the sprinkler type for fire service
• c.PVC drain pipe in Schedule 40 wall thickness
• d.Polyethylene irrigation tubing for landscape use

The standard approves PVC C900 of Class 150 or greater that is listed for such use. Drain pipe, irrigation tubing and CPVC sprinkler pipe are not listed underground fire service materials.Sacramento Metropolitan Fire District FPS 9

What does a plan design statement name, in the Moreno Valley guideline?

• a.The contractor's insurance carrier and policy
• b.The name of the building's major tenant
• c.The standards and editions used✓
• d.The total contract price for the project

The statement says the plans were designed in accordance with NFPA 24 and NFPA 13 editions, the California Fire Code and local code, and the manufacturers' requirements. Insurance, price and tenant are not part of it.Moreno Valley Fire Department guideline

What does the Sacramento Metropolitan standard want shown on the cover sheet of sprinkler plans about construction type?

• a.The total number of tenants and parking spaces in the building
• b.The date of the last roof inspection visit
• c.Whether the building has a basement level
• d.Whether construction is obstructed or unobstructed✓

The standard requires the cover sheet to note whether construction is obstructed or unobstructed, because that governs the coverage a sprinkler may be given. The tenant count has no bearing on coverage. The date of the last roof inspection is not plan information at all. A basement level is a building feature, not the obstructed or unobstructed classification.Sacramento Metropolitan Fire District FPS 1

Which civil sheet must accompany sprinkler submittals that need hydraulic calculations, in the Sacramento standard?

• a.The grading plan sheet
• b.The landscape irrigation plan sheet
• c.The roof plan of the building
• d.The approved civil water plan sheet✓

The standard requires the approved civil water plan sheet prepared by the civil engineer of record to accompany submittals that require hydraulic calculations. Grading, irrigation and roof sheets do not show the water supply.Sacramento Metropolitan Fire District FPS 1

Where is a copy of the private fire service underground plans kept, in the Sacramento standards?

• a.In the files of the owner's attorney and insurance carrier
• b.In the fire station files
• c.In the general contractor's job trailer
• d.In a document box by the sprinkler riser✓

The standards require a copy of the underground plans to be kept in a document box by the sprinkler riser, so later work can find it where it is needed. An attorney's office and the fire station files are places a fitter working at the riser cannot reach. A job trailer is gone when the project ends.Sacramento Metropolitan Fire District FPS 1 and FPS 9

What does the fire code say the exterior waterflow alarm device is activated by?

• a.Flow equal to the full design demand of the largest hazard
• b.Flow of one sprinkler of the smallest orifice✓
• c.A pressure loss of 10 psi at the riser
• d.Flow of at least 100 gpm at the riser

The alarm device is activated by water flow equivalent to the flow of a single sprinkler of the smallest orifice size in the system. It does not wait for the design demand, a fixed 100 gpm, or a pressure loss.2025 CFC 903.4.3

How must alarm, supervisory and trouble signals from a sprinkler system differ and travel, under the fire code?

• a.Distinct, and sent automatically to a supervising station✓
• b.Identical, and sounded locally at the riser and the front desk
• c.Identical, and sent when the fire department asks
• d.Distinct, but sent by phone call from occupants

Alarm, supervisory and trouble signals must be distinct and sent automatically to a supervising station, or sound at an approved constantly attended location. Identical signals cannot be told apart, and sounding them only at the riser does not reach anyone off the premises. Sending them only when the fire department asks is not automatic. Phone calls from occupants depend on a person noticing and are not an automatic transmission.2025 CFC 903.4.2

To what code section must the potable water supply to a sprinkler system be protected against backflow?

• a.Health and Safety Code 13114.7✓
• b.Government Code 4216
• c.Labor Code 6500
• d.Business and Professions Code 7026

The fire code cites Health and Safety Code 13114.7 for backflow protection of the potable supply. The Business and Professions, Labor and Government Code sections concern licensing, excavation permits and underground notification.2025 CFC 903.3.5

What does the Sacramento standard say about partially sprinklering a new building?

• a.Not allowed without the Fire Marshal's approval✓
• b.Required on the ground floor
• c.Allowed for one-story buildings under 10,000 square feet
• d.Allowed when the owner prefers

All new buildings that require sprinkler protection must have sprinklers throughout, and none may be partially protected without the Fire Marshal's approval. Requiring them on the ground floor only is a partial system, which is what the rule restricts. A size exemption for buildings under 10,000 square feet is not in the standard. The owner's preference is not a basis for leaving areas unprotected.Sacramento Metropolitan Fire District FPS 1

A light hazard room is 48 feet by 30 feet with a smooth, unobstructed noncombustible ceiling and limits of 225 square feet and 15 feet. What is the smallest grid that satisfies both limits?

• a.6 sprinklers, 3 by 2
• b.12 sprinklers, 4 by 3
• c.7 sprinklers, 7 by 1
• d.8 sprinklers, 4 by 2✓

The area is 1,440 square feet, so at least 7 sprinklers by area, but a rectangular grid also needs spacing of 15 feet or less: 4 across gives 12 feet and 2 down gives 15 feet, so 4 by 2 = 8 sprinklers at 180 square feet each. Seven cannot form a grid, 4 by 3 works but is not the smallest, and 3 by 2 would space them 16 feet apart and cover 240 square feet each.Consultant summary of NFPA 13 spacing limits

An ordinary hazard floor of 5,200 square feet uses standard spray sprinklers at the 130 square foot limit. Assuming the layout fits, how many sprinklers does coverage alone require?

• a.52
• b.26
• c.24
• d.40✓

5,200 ÷ 130 = 40. Dividing by 225 gives 23.1, which rounds up to 24; dividing by 100 gives 52; and dividing by 200 gives 26.Consultant summary of NFPA 13 spacing limits

A light hazard area of 6,300 square feet uses standard spray sprinklers at the 225 square foot limit. How many sprinklers does coverage alone require?

• a.28✓
• b.63
• c.32
• d.49

6,300 ÷ 225 = 28. Dividing by 130 gives 48.5, which rounds up to 49; dividing by 200 gives 31.5, which rounds up to 32; and dividing by 100 gives 63.Consultant summary of NFPA 13 spacing limits

A storeroom is 36 feet by 24 feet, ordinary hazard, limits 130 square feet and 15 feet. What is the smallest grid that satisfies both limits?

• a.6 sprinklers, 3 by 2
• b.9 sprinklers, 3 by 3
• c.7 sprinklers, 7 by 1
• d.8 sprinklers, 4 by 2✓

The area is 864 square feet and 864 ÷ 130 = 6.6, so at least 7 by area, but 7 cannot form a grid; 4 by 2 gives 8 sprinklers at 108 square feet each with spacings of 9 and 12 feet. A 3 by 2 grid would cover 144 square feet each, over the limit, and 3 by 3 works but is not the smallest.Consultant summary of NFPA 13 spacing limits

A system has 275 sprinklers. How many spares does the acceptance checklist call for?

• a.24, some of each type, with a wrench
• b.12, some of each type, with a wrench
• c.6, some of each type, with a wrench✓
• d.3, of one type, with a wrench

The checklist calls for 6 spares up to 300 sprinklers, 12 from 300 to 1,000 and 24 above 1,000, some of each type, with a wrench. Twelve and 24 are the larger tiers, and 3 spares of one type are fewer than required.Idaho State Fire Marshal acceptance checklist

A system has 720 sprinklers of three types. Which spare stock matches the checklist?

• a.6 spares, of the most common type
• b.12 spares, some of each type installed✓
• c.12 spares, of the same type
• d.24 spares, of the most common type

Between 300 and 1,000 sprinklers the checklist calls for 12 spares with some of each type installed, and a wrench. Six spares is the tier below 300 sprinklers, and it also fails the each-type requirement when limited to the most common type. Twelve spares of one type has the right count but the wrong mix, because a spare of one type cannot replace the others. Twenty-four is the tier above 1,000 sprinklers.Idaho State Fire Marshal acceptance checklist

A system will have 1,400 sprinklers and 4 types. How many spares does the checklist call for at minimum?

• a.36
• b.12
• c.24✓
• d.6

Above 1,000 sprinklers the checklist calls for 24 spares, with some of each type. Twelve is the tier for 300 to 1,000 sprinklers and six is the tier below 300. Thirty-six is not a figure in the checklist, and more types do not raise the count.Idaho State Fire Marshal acceptance checklist

For 1-1/2 inch pipe, what is the longest distance from the end sprinkler to the last hanger under the checklist?

• a.48 inches
• b.60 inches✓
• c.36 inches
• d.24 inches

The checklist allows 60 inches for 1-1/2 inch pipe and larger, 48 inches for 1-1/4 inch and 36 inches for 1 inch pipe. Twenty-four inches is not a stated limit.Idaho State Fire Marshal acceptance checklist

An estimator counts hangers for a branch line. What does the checklist say about spacing on a branch line?

• a.One hanger per section of pipe, with exceptions✓
• b.One hanger per sprinkler, without exceptions
• c.One hanger for each 50 feet of pipe
• d.One hanger at the end of the line

Branch lines have one hanger per section of pipe, with exceptions in the standard. One per sprinkler would over-hang short sections and is not the rule. A fixed one per 50 feet ignores the pipe sections and the maximum distance from the end sprinkler. A single hanger at the end of the line is a rule for mains and crossmains, in addition to one between branch lines, and one hanger cannot support a branch line.Idaho State Fire Marshal acceptance checklist

A fire main trench is 120 feet long, 3 feet wide and 4 feet deep. How many cubic yards of excavation?

• a.160
• b.53.3✓
• c.480
• d.1,440

120 × 3 × 4 = 1,440 cubic feet, and 1,440 ÷ 27 = 53.3 cubic yards. The figure 1,440 is cubic feet unconverted, 160 divides by 9, and 480 divides by 3.Estimating arithmetic (volume conversion)