C-16 Fire Protection exam questions, with answers
10 practice questions for the CSLB Fire Protection trade exam, each with the answer, a plain explanation and the source it rests on.
These are not real exam questions. CSLB does not release its test questions or answer keys, and nobody else has them. We write our own questions from the C-16 outline and the codes, standards and references CSLB lists for the exam. Each answer names its source so you can check it.
The C-16 exam has 5 sections. The questions below are grouped by section, with the share of the exam each one carries. Read the question, pick an answer, then open “Show the answer”. The other questions of the free test, scored section by section, are in the free 25-question C-16 test.
Planning and Estimating · 25% of the exam
Planning fire protection projects; estimating fire protection projects.
1. A developer asks you how the three NFPA sprinkler installation standards differ in purpose. According to MeyerFire's 2020 summary of NFPA 13, NFPA 13R and NFPA 13D, which list matches the stated objective of each standard?
- 13: property only; 13R: life safety and property; 13D: life safety and some property
- 13: life safety and property; 13R: life safety only; 13D: life safety and some property
- 13: life safety and property; 13R: life safety and some property; 13D: life safety only
- 13: life safety only; 13R: life safety and some property; 13D: life safety and property
Show the answer
Answer: C. The MeyerFire comparison lists the objective of NFPA 13 as life safety plus property protection, NFPA 13R as life safety plus some property protection, and NFPA 13D as life safety only. That is why 13R and 13D allow more omitted areas than NFPA 13. The other lists swap the goals between the standards.
Source: MeyerFire comparison table, Code planning: Objective (NFPA 13, 13R, 13D, 2002-2019 editions)
2. An owner wants 1-1/2 in. occupant hose stations (a Class II standpipe) added to a new office building's sprinkler and standpipe job 'to be safe.' According to NFSA's article on NFPA 14 and NFPA 13 hose connections, what is the current status of Class II standpipes?
- Obsolete, with no current code requirement to install them
- Required on every floor of buildings over four stories tall
- Required wherever a Class I standpipe system is installed
- Required in place of Class I where there is no FDC inlet
Show the answer
Answer: A. NFSA explains that Class II standpipes are obsolete, were meant for trained fire brigades fighting incipient fires, and do not supply the flow needed for interior structural firefighting. It also states there is currently no code requirement to install a Class II standpipe. The fire department relies on the 2-1/2 in. Class I connections instead.
Source: NFSA article on NFPA 14 standpipe classes: Class II standpipes obsolete, no code requirement
Installation of Underground Fire Main Systems · 9% of the exam
Trenching and shoring excavations; installing pipes and thrust blocks; installing fire hydrants and fire department connections (FDC).
3. Your designer schedules a hydrant flow test on the public main for a new sprinkler job. Under NFPA 291 (2022 edition) 4.3.1, as QRFS reports the change from the 2019 edition, when should the test be conducted?
- During periods of lowest demand, such as late at night or on weekends
- At any time of day, since the results are adjusted to 20 psi residual
- During periods of peak demand, based on knowledge of the water supply
- During periods of ordinary demand, as the 2019 edition recommended
Show the answer
Answer: C. QRFS reports that NFPA 291 (2022) 4.3.1 now suggests running hydrant flow tests during periods of peak demand, based on knowledge of the water supply and engineering judgment, replacing the 2019 advice to test during ordinary demand. Peak-demand testing reflects the weakest supply the system may see in a fire. Testing at night gives optimistic results.
Source: NFPA 291 (2022) 4.3.1 timing of flow tests (peak demand), as reported by QRFS
4. Your crew is assembling a mechanical joint on a ductile iron fire main that must turn slightly to follow a curved property line. According to DIPRA's installation guide for ductile iron pipe, when is the joint deflected?
- After the joint is assembled, but before the bolts are tightened
- After the bolts are torqued to the normal range for the gland
- Before the plain end enters the bell, then assembled at the angle
- After the backfill is placed and compacted to the pipe springline
Show the answer
Answer: A. DIPRA's guide says pipe should be assembled in a straight line before deflection is made, and for mechanical joints the deflection is made after joint assembly but before tightening the bolts, with the bolts only hand tight. Inserting a plain end into a bell at an angle should be avoided. Deflecting after torquing or after backfill can damage the joint or leave it unseated.
Source: DIPRA installation guide, mechanical joint assembly and 3.9 Joint Deflection
Installation of Fire Protection Systems · 36% of the exam
Installing fire sprinkler systems; installing preaction and deluge systems; installing storage tanks and fire pumps; installing fire suppression systems.
5. A wide duct forces you to add sprinklers below it on an NFPA 13 (2025) job, and the 2025 edition now calls these 'supplemental sprinklers.' According to QRFS's review of the new rules, what response type should they be?
- Quick response, or otherwise with fast-response elements
- Residential, since each one covers a small area under the duct
- Standard response, rated one temperature class above the ceiling
- Standard response, so they do not open before ceiling heads
Show the answer
Answer: A. QRFS reports that the NFPA 13 (2025) rules call for supplemental sprinklers to be quick-response or otherwise have fast-response elements (ESFR in storage, for example). They should generally match the ceiling sprinklers' K-factor, orientation and coverage type, and need water shields in some locations. Standard-response or residential heads do not meet the new rule.
Source: NFPA 13 (2025) supplemental sprinklers (3.3.223.3.6, 9.5.5.3.3), as described by QRFS
6. A new riser's main drain must pass through an exterior wall to discharge outdoors, where the pipe could freeze. Under NFPA 13 (2025 edition) 16.10.4.9, how much exposed drain pipe must be left in the heated area between the drain valve and the wall?
- At least 6 ft
- At least 2 ft
- At least 1 ft
- At least 4 ft
Show the answer
Answer: D. NFPA 13 (2025 edition) 16.10.4.9 says that where a drain pipe passes through an exterior wall, at least 4 ft of exposed drain pipe must be left in the heated area between the valve and the wall. The warm length keeps the water held near the valve from freezing. A 1 ft or 2 ft run is too short, and 6 ft is not the stated minimum.
Maintenance and Repair of Fire Protection Systems · 9% of the exam
Inspecting and troubleshooting fire protection equipment; repairing fire protection equipment; maintaining fire protection equipment.
7. A building owner wants the maintenance engineer, a trained employee, to do the routine sprinkler system inspections in-house instead of hiring a service company. Under 19 CCR 904.1(a), what applies?
- The employee may inspect only if a licensed firm signs each report
- The employee needs a C-16 license or must work under a C-16 holder
- The employee needs a State Fire Marshal 'A' license before inspecting
- No license, if the employee is competent by training and experience
Show the answer
Answer: D. 19 CCR 904.1(a) says a license is not required to perform inspections; an employee designated by the owner or occupant who has developed competence through training and experience may do them. The exception is a business that inspects for a fee, which needs a State Fire Marshal 'A' license or a CSLB C-16 license. Testing and maintenance have their own licensing rules.
8. During an annual test you find that a building's sprinklers are a recalled product, and the owner orders replacements. Under 19 CCR 904.1(c), how must the replacement sprinklers be installed?
- Per the listing, the maker's instructions and the NFPA installation standards
- Per the original working plans, without regard to the current listing
- Per the local AHJ's choice, after a full hydrostatic retest of the system
- Per the recall notice alone, since it supersedes the installation standards
Show the answer
Answer: A. 19 CCR 904.1(c) requires recalled products to be replaced or remedied, and the replacement or remedial product to be installed in accordance with the listing requirements, the manufacturer's instructions and the appropriate NFPA installation standards. The owner or occupant must promptly correct deficiencies found during inspection, testing and maintenance. Old plans or the recall notice alone do not replace those three references.
Source: 19 CCR 904.1(c), correction of deficiencies and installation of replacements for recalled products
Safety · 21% of the exam
Personnel safety; job site safety; underground work.
9. Your crew is laying an underground fire main outdoors on a summer afternoon. Under 8 CCR 3395(d)(1), above what outdoor temperature must the employer keep shade present at all times while employees are there?
- 75°F
- 80°F
- 85°F
- 95°F
Show the answer
Answer: B. 8 CCR 3395(d)(1) requires shade to be present when the outdoor temperature in the work area exceeds 80°F, enough for the employees on rest or recovery periods, as close as practicable to the work. At or below 80°F the employer may provide timely access to shade on request instead. 95°F is the trigger for the high-heat procedures, a different rule.
Source: 8 CCR 3395(d)(1), shade present when the temperature exceeds 80 degrees Fahrenheit
10. On a new construction site, your fitter plugs a pipe threading machine into a 120-volt, 20-ampere receptacle on a temporary power distribution box that is not part of the building's permanent wiring. Under 8 CCR 2405.4(c), what protection must that receptacle have?
- A breaker sized below the threading machine's nameplate current
- An approved ground-fault circuit interrupter for personnel protection
- An arc-fault circuit interrupter listed for temporary construction use
- A locking cap so the plug cannot be pulled out while under load
Show the answer
Answer: B. 8 CCR 2405.4(c) requires all 120-volt, single-phase, 15- and 20-ampere receptacle outlets on construction sites that are not part of the permanent wiring and are used by employees to have approved ground-fault circuit interrupters for personnel protection. A GFCI on the feeder is also allowed. Arc-fault devices, locking caps or breaker sizing do not meet the rule.
Source: 8 CCR 2405.4(c), GFCI protection for temporary 120 V 15/20 A receptacles on construction sites
Where to go from here
How the license works, from experience to fees: how to get a C-16 license. Everything about the course: the C-16 exam page.
Questions from our free C-16 test, written from CSLB License Examination Study Guide, Fire Protection (C-16), form 13E-16 (03-2026), for examinations scheduled on or after January 26, 2022. CSLB notes that the percentages are approximate. Reviewed 14 October 2026. Study guidance only; we are not affiliated with CSLB or PSI.