FDNY s15 Supervision Of Foam-Water
Sprinkler Systems (Citywide) Exam
Questions And Correct Answers With
Rationales 2026
1. What is the primary purpose of a foam-water sprinkler system?
A. To suppress Class A fires only
B. To control and extinguish flammable liquid (Class B) fires
C. To provide cooling only
D. To detect fires through heat sensors
Rationale: Foam-water systems are designed for Class B hazards involving
flammable liquids by forming a foam blanket that suppresses vapors and
cools surfaces._
2. What foam type is most commonly used in foam-water sprinkler
systems protecting hydrocarbon fuels?
A. AFFF (Aqueous Film Forming Foam)
,B. Protein foam
C. Alcohol-resistant foam
D. Fluoroprotein foam
Rationale: AFFF forms a thin film that rapidly spreads over hydrocarbon
fuel surfaces, providing quick vapor suppression._
3. Alcohol-resistant foams are specifically designed for what type of fuels?
A. Hydrocarbons
B. Polar solvents
C. Combustible solids
D. Organic peroxides
Rationale: Polar solvents dissolve regular foams, so alcohol-resistant foam
creates a polymer membrane to protect the foam layer._
4. Which component mixes foam concentrate with water in the proper
proportion?
A. Foam nozzle
B. Foam proportioner
C. Foam generator
D. Concentrate pump
Rationale: The proportioner ensures the correct concentrate-to-water
ratio, essential for foam effectiveness._
,5. What is the standard foam concentrate proportion for AFFF in most
systems?
A. 1%
B. 3% or 6%
C. 10%
D. 15%
Rationale: AFFF concentrates are formulated for 3% or 6% mixtures,
depending on hazard type and manufacturer._
6. Which NFPA standard governs foam-water sprinkler systems?
A. NFPA 13
B. NFPA 16
C. NFPA 25
D. NFPA 30
Rationale: NFPA 16 provides installation and maintenance standards for
foam-water sprinkler and spray systems._
7. Foam-water sprinkler systems are classified as what type of system
under NFPA 16?
A. Hybrid fire protection system
B. Dry chemical system
, C. Standpipe system
D. Gaseous suppression system
Rationale: Foam-water systems combine properties of foam and water
systems, making them hybrid systems._
8. The main extinguishing action of foam is by:
A. Cooling the fire area
B. Diluting fuel concentration
C. Smothering and separating the fuel from oxygen
D. Increasing air humidity
Rationale: Foam isolates the fuel surface from air, suppressing vapor and
oxygen contact._
9. Which type of foam system is automatically activated by a heat detector
network?
A. Foam-water sprinkler system
B. Manual foam monitor system
C. Mobile foam unit
D. Portable extinguisher system
Rationale: Foam-water sprinkler systems use detection and activation
similar to standard automatic sprinklers._
Sprinkler Systems (Citywide) Exam
Questions And Correct Answers With
Rationales 2026
1. What is the primary purpose of a foam-water sprinkler system?
A. To suppress Class A fires only
B. To control and extinguish flammable liquid (Class B) fires
C. To provide cooling only
D. To detect fires through heat sensors
Rationale: Foam-water systems are designed for Class B hazards involving
flammable liquids by forming a foam blanket that suppresses vapors and
cools surfaces._
2. What foam type is most commonly used in foam-water sprinkler
systems protecting hydrocarbon fuels?
A. AFFF (Aqueous Film Forming Foam)
,B. Protein foam
C. Alcohol-resistant foam
D. Fluoroprotein foam
Rationale: AFFF forms a thin film that rapidly spreads over hydrocarbon
fuel surfaces, providing quick vapor suppression._
3. Alcohol-resistant foams are specifically designed for what type of fuels?
A. Hydrocarbons
B. Polar solvents
C. Combustible solids
D. Organic peroxides
Rationale: Polar solvents dissolve regular foams, so alcohol-resistant foam
creates a polymer membrane to protect the foam layer._
4. Which component mixes foam concentrate with water in the proper
proportion?
A. Foam nozzle
B. Foam proportioner
C. Foam generator
D. Concentrate pump
Rationale: The proportioner ensures the correct concentrate-to-water
ratio, essential for foam effectiveness._
,5. What is the standard foam concentrate proportion for AFFF in most
systems?
A. 1%
B. 3% or 6%
C. 10%
D. 15%
Rationale: AFFF concentrates are formulated for 3% or 6% mixtures,
depending on hazard type and manufacturer._
6. Which NFPA standard governs foam-water sprinkler systems?
A. NFPA 13
B. NFPA 16
C. NFPA 25
D. NFPA 30
Rationale: NFPA 16 provides installation and maintenance standards for
foam-water sprinkler and spray systems._
7. Foam-water sprinkler systems are classified as what type of system
under NFPA 16?
A. Hybrid fire protection system
B. Dry chemical system
, C. Standpipe system
D. Gaseous suppression system
Rationale: Foam-water systems combine properties of foam and water
systems, making them hybrid systems._
8. The main extinguishing action of foam is by:
A. Cooling the fire area
B. Diluting fuel concentration
C. Smothering and separating the fuel from oxygen
D. Increasing air humidity
Rationale: Foam isolates the fuel surface from air, suppressing vapor and
oxygen contact._
9. Which type of foam system is automatically activated by a heat detector
network?
A. Foam-water sprinkler system
B. Manual foam monitor system
C. Mobile foam unit
D. Portable extinguisher system
Rationale: Foam-water sprinkler systems use detection and activation
similar to standard automatic sprinklers._
