Fire-Inspector-II Practice Exam Questions with Answers 67 - Fire Inspector II Exam Certification

Seating Arrangements for Large Assembly Events

According to the International Fire Code (IFC) 2021, Section 1029.14, when more than 500 chairs are used for an assembly event held in a gymnasium (or similar venue), they must be either:

Secured to the floor OR

Fastened together in groups of at least three (3) chairs.

2. Why Groups of 3 is the Correct Answer

This requirement ensures organized seating, preventing chairs from shifting or obstructing aisles during emergencies.

Properly fastened chairs reduce the risk of crowd-related hazards, ensuring safe and efficient evacuation if needed.

3. Verification of Other Options

Option A (spaced at least 6 inches apart) – Incorrect, as the IFC requires chairs to be fastened together or secured when over 500 are used.

Option C (groups of not less than 6) – Incorrect, as the minimum required grouping is 3.

Option D (groups of not less than 10) – Incorrect, as the IFC does not mandate groups of 10.

Reference Sources:

International Fire Code (IFC) 2021 – Section 1029.14 (Seating and Fastening Requirements for Assembly Events)

NFPA 101: Life Safety Code (Seating Arrangements in Assembly Occupancies)

ICC Fire Inspector II Study Guide (2021)

? Reference to Occupant Load Factor Calculations:

The International Fire Code (IFC 2021), Table 1004.5 provides occupant load factors for different types of occupancies.

For assembly occupancy with tables and chairs, the occupant load factor is 15 square feet per person (net area).

? Calculation of Occupant Load:

Formula: Occupant Load=Net Square FootageOccupant Load Factor\text{Occupant Load} = \frac{\text{Net Square Footage}}{\text{Occupant Load Factor}}Occupant Load=Occupant Load FactorNet Square Footage?

Given: 2,500 net square feet, with a load factor of 15 sq. ft. per person: 250015=166.67?167 occupants\frac{2500}{15} = 166.67 \approx 167 \text{ occupants}152500?=166.67?167 occupants

? Clarification of Incorrect Answer Choices:

A. 167 ? Correct

Matches the exact IFC Table 1004.5 calculation.

B. 227 ? Incorrect

Would correspond to a lower load factor (about 11 sq. ft. per occupant), which is not the standard for tables and chairs.

C. 357 ? Incorrect

Would correspond to a 7 sq. ft. per occupant factor, used for tighter seating arrangements (e.g., assembly without fixed seats).

D. 500 ? Incorrect

Would correspond to a 5 sq. ft. per occupant factor, typically used for standing areas or dense seating arrangements.

? Conclusion:

The correct and verified answer is A (167 occupants) based on IFC Table 1004.5, using the standard occupant load factor for assembly occupancies with tables and chairs.

? Reference to Elevator Safety and Firefighter Use:

ASME A17.1 (Safety Code for Elevators and Escalators) establishes the safety requirements for elevators, including those designated for firefighter and emergency personnel use.

The International Fire Code (IFC) and NFPA 101 (Life Safety Code) both reference ASME A17.1 when addressing elevator safety and firefighter access.

? Firefighter Access and Operation Requirements:

ASME A17.1, Section 2.27 covers Firefighter Emergency Operations (FEO), which includes:

Phase I Operation (Automatic recall of elevators to a designated floor upon activation of fire alarms).

Phase II Operation (Manual override by firefighters for rescue and suppression operations).

IFC 607.1 (2021 Edition) mandates that fire service access elevators comply with ASME A17.1 for firefighter use in high-rise and multi-story buildings.

? Clarification of Incorrect Answer Choices:

A. UL 803 ? Incorrect

UL 803 is not related to elevator fire safety; it pertains to electrical control panels for industrial applications.

B. NFPA 70 (National Electrical Code) ? Incorrect

While NFPA 70 covers electrical wiring and circuits, it does not specifically regulate elevator emergency operations.

D. ASME A17.3 ? Incorrect

ASME A17.3 is the Safety Code for Existing Elevators and Escalators, which applies to retrofits and upgrades, but ASME A17.1 is the primary code for operational and emergency use elevators.

? Conclusion:

The correct and verified answer is C (ASME A17.1) because it specifically outlines the requirements for firefighter and emergency personnel elevator use, ensuring compliance with the IFC and NFPA codes.

All new building construction must have an approved water supply that meets the minimum fire flow requirements necessary for fire protection. The exact fire flow depends on factors such as building size, occupancy type, construction materials, and hazard levels.

Reference to Fire Inspector Documentation:

1. 2021 International Fire Code (IFC) – Section 507.1 (Required Water Supply)

IFC 507.1 states that an approved water supply capable of providing the required fire flow must be installed in all new construction projects.

The required fire flow varies based on building classification and must be determined by the authority having jurisdiction (AHJ).

2. 2021 IFC – Appendix B (Fire-Flow Requirements for Buildings)

Table B105.1(2) provides fire flow requirements based on construction type and building area.

Fire flow must be calculated according to the ISO (Insurance Services Office) Fire Suppression Rating Schedule.

Detailed Explanation of Answer Choices:

Option A (Correct): The fire flow requirement is determined based on the building and fire protection needs, making this the correct answer.

Option B (Incorrect): A static pressure of 40 psi at each hydrant is not a universal requirement, as fire flow is the primary factor.

Option C (Incorrect): A static pressure of 60 psi is not the fire code’s general requirement; fire flow is the priority.

Option D (Incorrect): 250 gallons per minute (GPM) at a fire-access outlet is not an overall fire code requirement for all buildings—it depends on the structure’s classification.

Thus, the correct and verified answer is: A. The required fire flow for fire protection.

? Reference to Fire Extinguisher Requirements in Buildings Under Construction:

NFPA 241 (Standard for Safeguarding Construction, Alteration, and Demolition Operations) Section 13.6.1 and IFC 3309.1 require that:

A minimum of one fire extinguisher per floor is required.

Additional extinguishers are required based on stairwells and floor area.

If a building under construction has two stairways, a minimum of two fire extinguishers must be provided per floor to ensure adequate fire protection coverage.

? Fire Safety Considerations for Construction Sites:

Construction sites pose a high fire risk due to temporary electrical systems, combustible materials, and lack of finished fire suppression systems.

Fire extinguishers must be readily available and evenly distributed near exit stairways and pathways for rapid access in case of an emergency.

? Clarification of Incorrect Answer Choices:

A. 1 ? Incorrect

One extinguisher is the minimum required for floors with only one exit/stairway, but a building with two stairways requires at least two extinguishers.

C. 3 ? Incorrect

While more extinguishers can be added for larger areas or high-risk work zones, the minimum requirement remains two for two stairwells.

D. 4 ? Incorrect

There is no general requirement for four extinguishers per floor unless dictated by floor size and hazard level.

? Conclusion:

The correct and verified answer is B (2 fire extinguishers per floor) based on NFPA 241 and IFC 3309.1, ensuring compliance with fire safety standards for buildings under construction.

The interior finish requirements for walls and ceilings in an atrium are regulated under the 2021 International Building Code (IBC), Section 404 – Atriums, and Table 803.11 – Interior Wall and Ceiling Finish Requirements.

IBC Section 404.8 – Interior Finish in Atriums:

"The interior finish of walls and ceilings in an atrium shall be not less than Class A."

Class A interior finishes have the highest level of fire resistance and low flame spread to minimize fire hazards in large open spaces like atriums.

Class A Interior Finish Ratings (Per ASTM E84 and NFPA 286):

Flame Spread Index: 0 – 25

Smoke Developed Index: 0 – 450

Why Other Options Are Incorrect?

B. Class B – Less fire-resistant than Class A, not permitted for atriums.

C. Class C – Provides even lower fire protection, making it unsuitable.

D. Class D – Not recognized as an acceptable interior finish classification for atriums.

? Reference to Occupant Load Calculation:

The International Fire Code (IFC 2021), Section 1004.2 states that the calculated occupant load of a building may be increased if all other life safety provisions are met.

However, the occupant load cannot exceed one person per 5 square feet when increased beyond the standard calculations.

? Fire Safety Considerations for Increased Occupant Load:

Increasing the occupant load requires ensuring:

Egress capacity (number and width of exits) meets the increased load.

Fire protection systems (sprinklers, alarms, etc.) are adequate for the new load.

Proper ventilation and sanitation facilities are maintained.

IFC 1004.2 and NFPA 101 both enforce the maximum limit of 1 occupant per 5 square feet in modified occupant load scenarios.

? Clarification of Incorrect Answer Choices:

A. 3 sq. ft. ? Incorrect

Too small for safe egress and occupant movement; the code does not allow such high density in general occupancies.

C. 7 sq. ft. ? Incorrect

While some occupancies have higher space-per-occupant allowances, 5 sq. ft. is the maximum density permitted when increasing load.

D. 15 sq. ft. ? Incorrect

15 sq. ft. per person is for lower-density assembly and business occupancies, not for maximum occupant load increases.

? Conclusion:

The correct and verified answer is B (5 sq. ft. per occupant) as per IFC 1004.2 and NFPA 101, which govern occupant load increases in buildings.

? Reference to ICC Fire Code Regulations:

According to the International Fire Code (IFC) Section 308.1.5 (2021 Edition), the use of open-flame devices, including candles, is prohibited in dormitories, sleeping rooms, and similar occupancies unless specifically approved by the fire code official.

The regulation exists to prevent fire hazards in areas with high occupant density and potentially limited egress routes.

? Fire Safety Concerns in Dormitories:

Dormitories typically contain highly combustible materials such as bedding, curtains, and furniture, making them susceptible to rapid fire spread.

The presence of multiple residents in a shared living space increases the risk of fire-related casualties.

Even in sprinklered buildings, candles pose an unnecessary ignition risk that could endanger occupants before the activation of fire suppression systems.

? Clarification of Incorrect Answer Choices:

B. may be used in a sprinklered dormitory ? Incorrect

While fire sprinklers help control fires, they do not prevent ignition, and the prohibition still applies regardless of sprinkler systems.

C. must be kept a minimum of 12 inches from combustibles ? Incorrect

This rule applies to general open-flame devices in some circumstances but does not override the outright ban on candles in dormitories.

D. must be kept a minimum of 36 inches from combustibles ? Incorrect

Similar to option C, maintaining a distance from combustibles does not exempt candles from being prohibited in dormitory settings.

? Conclusion:

The correct and verified answer is A (Candles may not be used) based on the International Fire Code (IFC) Section 308.1.5, ensuring fire safety compliance in dormitory settings.

According to the 2021 International Fire Code (IFC) and the International Building Code (IBC) Section 1014.3, handrails are categorized into Type I and Type II based on their shape and size requirements.

Type I handrails refer to those that are not circular in shape but still comply with graspability requirements.

IBC Section 1014.3.1 states that:

If a handrail is not circular, it must have a perimeter dimension between 4 inches (minimum) and 6.25 inches (maximum).

The cross-section of such a handrail should provide an adequate grasping surface.

? Correct Answer: D. 6.25 inches

LP-Gas Storage Limits for Dealers in Non-Public Buildings

According to the International Fire Code (IFC) 2021, Section 6109.9, the maximum allowable quantity of LP-gas in containers stored by a dealer awaiting resale in a building that is not open to the public is 2,000 pounds of water capacity.

This limit is intended to reduce fire and explosion hazards in enclosed spaces while allowing reasonable storage for commercial purposes.

2. Understanding Water Capacity vs. Propane Weight

The water capacity of an LP-gas cylinder refers to the total weight of water the container can hold, not the actual propane content.

The propane content is typically about 42% of the water capacity (i.e., 2,000 lbs. of water capacity is approximately 840 lbs. of propane).

3. Verification of Other Options

Option A (735 lbs.) – Incorrect, as IFC allows a significantly higher storage limit for dealers in non-public buildings.

Option B (1,000 lbs.) – Incorrect, as the actual limit per IFC 6109.9 is 2,000 lbs.

Option D (2,500 lbs.) – Incorrect, as this exceeds the IFC's maximum allowable storage limit.

Reference Sources:

International Fire Code (IFC) 2021 – Section 6109.9 (LP-Gas Storage Limits in Buildings Not Open to the Public)

NFPA 58: Liquefied Petroleum Gas Code (LP-Gas Storage and Handling Guidelines)

ICC Fire Inspector II Study Guide (2021)

Battery-charging areas for industrial trucks (such as forklifts) present a fire hazard due to the potential for flammable hydrogen gas buildup and electrical malfunctions. To mitigate this risk, portable fire extinguishers with a minimum rating of 40-B:C are required.

Reference to Fire Inspector Documentation:

1. 2021 International Fire Code (IFC) – Section 309.5 (Fire Extinguishers for Battery-Charging Areas)

IFC 309.5 states that battery-charging areas must have a portable fire extinguisher with a minimum rating of 40-B:C to handle potential electrical and flammable liquid fires.

The B rating covers flammable liquid fires (such as battery electrolyte leaks), while the C rating ensures it is safe for electrical fires.

2. NFPA 10 – Standard for Portable Fire Extinguishers (2022 Edition)

NFPA 10, Table 6.3.1.1 outlines that industrial battery-charging areas must have at least one extinguisher rated 40-B:C.

This ensures adequate fire suppression capability for both electrical and flammable liquid hazards.

Detailed Explanation of Answer Choices:

Option A (Incorrect): 4-A:20-B:C includes a higher A-rating (for ordinary combustibles), but 20-B:C is below the required 40-B:C.

Option B (Incorrect): 3-A:40-B:C exceeds the B:C requirements but adds an unnecessary A-rating, which is not specified in the code.

Option C (Incorrect): 2-A:10-B:C is insufficient, as it does not meet the 40-B:C minimum requirement.

Option D (Correct): 40-B:C is the correct and minimum required rating per IFC 309.5 and NFPA 10.

Thus, the correct and verified answer is: D. 40-B:C.

High-Pile Combustible Storage Permit Requirements

According to the International Fire Code (IFC) 2021, Section 105.6.23, a permit is required for the storage of high-pile combustible stock when the storage area exceeds 2,500 square feet.

2. Definition of High-Pile Storage

High-pile storage is defined as storage of combustible materials on racks or piles exceeding 12 feet in height (or 6 feet for highly combustible materials, such as rubber and plastics).

IFC Table 3206.2 establishes fire protection requirements based on storage height, area, and commodity class.

3. Verification of Other Options

Option A (225 sq. ft.) – Incorrect, as this is far below the 2,500 sq. ft. permit threshold.

Option B (500 sq. ft.) – Incorrect, as the fire code does not require a permit at this level.

Option C (1,000 sq. ft.) – Incorrect, as the IFC specifies 2,500 sq. ft. as the threshold for requiring a permit.

Reference Sources:

International Fire Code (IFC) 2021 – Section 105.6.23 (High-Pile Combustible Storage Permit Requirements)

IFC Chapter 32 (High-Piled Storage Regulations)

ICC Fire Inspector II Study Guide (2021)

Thus, the correct and verified answer is: D. 2,500. ?

IFC Section 3804.1 classifies aerosol storage as Group H (high-hazard) if flammable, fitting option A. Options B and C are subgroups (H-2, H-3), while D (Group S-1) is for moderate-hazard storage, not applicable. This is consistent with the study guide's occupancy classifications.

References: Fire Inspector II Study Guide, IFC Section 3804.1.

Minimum Working Space Width for Electrical Equipment Panels

According to National Electrical Code (NEC) 110.26(A)(2) and International Fire Code (IFC) 2021, Section 604.3, the minimum working space width for electrical equipment must be at least the width of the equipment or 30 inches, whichever is greater.

Since the equipment panel in the question is 66 inches wide, the required working space width must be at least 66 inches.

2. Why 66 Inches is the Correct Answer

The minimum clearance width must be equal to the width of the electrical equipment if the panel itself is wider than 30 inches.

This ensures safe maintenance and emergency access to electrical components.

3. Verification of Other Options

Option A (30 inches) – Incorrect, because the equipment is wider than 30 inches, requiring a larger clearance.

Option B (36 inches) – Incorrect, as this is not the requirement for a 66-inch-wide panel.

Option D (78 inches) – Incorrect, as the clearance does not need to exceed the width of the panel.

Reference Sources:

National Electrical Code (NEC) 2023 – Section 110.26(A)(2) (Working Space Width Requirements)

International Fire Code (IFC) 2021 – Section 604.3 (Electrical Equipment Clearance Requirements)

ICC Fire Inspector II Study Guide (2021)

1. Standpipe Requirements in Construction

According to International Fire Code (IFC) 2021, Section 3313.1, a temporary standpipe must be installed when construction progresses above 75 feet from the lowest level of fire department access.

This ensures firefighters have adequate water supply access during high-rise construction.

2. Why the 75-Foot Requirement?

Buildings exceeding 75 feet are classified as high-rise structures, where fire department hose streams may not reach upper levels efficiently.

A standpipe system provides a reliable water source for fire suppression during construction, reducing fire risk.

3. Verification of Other Options

Option A (30 feet) – Incorrect, as standpipes are not required at this height under IFC regulations.

Option B (40 feet) – Incorrect, as this is below the high-rise threshold and does not require standpipes yet.

Option C (55 feet) – Incorrect, as IFC specifically mandates standpipes at 75 feet, not 55 feet.

Reference Sources:

International Fire Code (IFC) 2021 – Section 3313.1 (Temporary Standpipe Requirements for Construction)

NFPA 14: Standard for the Installation of Standpipes and Hose Systems

ICC Fire Inspector II Study Guide (2021)

Thus, the correct and verified answer is: D. 75 feet. ?

IFC Section 901.5 (Acceptance Tests) requires fire protection systems, including fire alarms, to be tested upon completion to ensure compliance with NFPA 72 (National Fire Alarm and Signaling Code) and the IFC. The contractor’s verification of full compliance (B) signals readiness for the official acceptance test by the fire code official, ensuring all components are installed and functional. Option A (zone-by-zone testing) is impractical for final acceptance. Option C ties the test to water supply, irrelevant to alarms. Option D (one year) is excessive and not required by IFC or NFPA 72 for initial acceptance. Thus, B is correct.

A code official may allow the occupant load to exceed the building code requirements if additional exit facilities are provided, all egress requirements are met, and the maximum occupancy does not exceed one occupant per 10 sq. ft. of occupiable floor area.

Reference to Fire Inspector Documentation:

1. 2021 International Building Code (IBC) – Table 1004.5 (Occupant Load Factor)

The minimum safe occupancy load factor is 10 sq. ft. per occupant, meaning no space can have more than 1 person per 10 sq. ft.

Fire code officials can approve increased occupancy only if extra exits are provided, ensuring compliance with egress and fire safety rules.

2. 2021 International Fire Code (IFC) – Section 1004.2 (Increased Occupant Load Allowance)

Allows for an increased occupant load only if additional exits and egress requirements are met but never beyond 1 person per 10 sq. ft.

Detailed Explanation of Answer Choices:

Option A (Incorrect): 1 occupant per 3 sq. ft. is too high and would violate egress safety regulations.

Option B (Incorrect): 1 occupant per 5 sq. ft. still exceeds safety limits.

Option C (Incorrect): 1 occupant per 7 sq. ft. is not the minimum required standard.

Option D (Correct): 1 occupant per 10 sq. ft. is the minimum limit for allowing an increased occupant load under IFC 1004.2 and IBC Table 1004.5.

Thus, the correct and verified answer is: D. 10.

Retention of Fire Code-Related Records

According to the International Fire Code (IFC) 2021, Section 104.6, records related to code enforcement decisions, including modifications or substitutions (such as a sprinkler system replacing a second exit), must be retained for as long as the building and the condition exist.

This ensures that future inspections, property owners, and authorities can verify past decisions and compliance history.

2. Why the Records Must Be Retained Permanently

Modifications that impact life safety (such as exit requirements) must remain on record for the lifetime of the building to ensure ongoing compliance and safety.

If the condition (sprinkler substitution for an exit) still exists, any future inspector or building official must be able to verify the original approval and rationale.

3. Verification of Other Options

Option A (Five years) – Incorrect, as fire code modifications must remain on record permanently if they affect egress or fire protection systems.

Option B (Three years) – Incorrect, as this timeframe applies to temporary inspection reports, not major code modifications.

Option C (Until the building is sold) – Incorrect, as ownership changes do not affect the need for record retention on fire safety decisions.

Reference Sources:

International Fire Code (IFC) 2021 – Section 104.6 (Fire Code Record Retention Requirements)

NFPA 1: Fire Code (Retention of Code-Related Decisions)

ICC Fire Inspector II Study Guide (2021)

Thus, the correct and verified answer is: D. For as long as the building and the condition exist. ?

To determine the maximum number of students permitted in a classroom, we must follow the occupant load calculation based on the 2021 International Building Code (IBC) and International Fire Code (IFC).

Step 1: Calculate the Room Area

The classroom measures 20 ft. x 30 ft., so the total area is:

20×30=600 sq. ft.20 \times 30 = 600 \text{ sq. ft.}20×30=600 sq. ft.

Step 2: Subtract the Area Occupied by Fixed Tables

Each table measures 4 ft. x 8 ft., so its area is:

4×8=32 sq. ft. per table4 \times 8 = 32 \text{ sq. ft. per table}4×8=32 sq. ft. per table

Since there are 4 tables:

32×4=128 sq. ft. occupied by tables32 \times 4 = 128 \text{ sq. ft. occupied by tables}32×4=128 sq. ft. occupied by tables

Step 3: Determine the Usable Space for Students

600?128=472 sq. ft. available600 - 128 = 472 \text{ sq. ft. available}600?128=472 sq. ft. available

Step 4: Apply the Occupant Load Factor

According to 2021 IBC Table 1004.5 (Occupant Load Factor), the factor for a classroom with tables and chairs is 20 sq. ft. per person.

472÷20=23.6472 \div 20 = 23.6472÷20=23.6

Since the occupant load must be rounded down, the maximum number of students is 24.

Reference to Fire Inspector Documentation:

1. 2021 International Building Code (IBC) – Table 1004.5 (Occupant Load Factor)

A classroom with tables and chairs requires 20 sq. ft. per occupant.

This method ensures compliance with egress and fire safety requirements.

2. 2021 International Fire Code (IFC) – Section 1004.1 (Occupant Load Determination)

The IFC states that occupant load is based on net usable floor area and must follow IBC Table 1004.5.

Detailed Explanation of Answer Choices:

Option A (Incorrect): 12 students would be too low based on the calculations.

Option B (Correct): 24 students is the accurate calculation following IBC 1004.5.

Option C (Incorrect): 30 students would exceed the available space per code.

Option D (Incorrect): 40 students is far above the allowed maximum.

Thus, the correct and verified answer is: B. 24.

Flammable Liquid Storage Limits in Control Areas

According to the International Fire Code (IFC) 2021, Section 5003.1.1 and Table 5003.1.1(1), the allowable quantity of flammable liquids stored in a control area can be doubled if the building is equipped with an automatic sprinkler system that complies with NFPA 13.

2. Why Automatic Sprinklers Allow Increased Storage

A sprinkler system significantly reduces fire risk by suppressing flames early, thus allowing greater quantities of hazardous materials to be safely stored.

IFC and NFPA 30 (Flammable and Combustible Liquids Code) specify that sprinkler-protected buildings can have up to twice the standard storage limits.

3. Verification of Other Options

Option A (permission is granted by the chief) – Incorrect, as storage limits are regulated by the fire code, not discretionary approval from the fire chief.

Option B (the control area exceeds 50,000 sq. ft.) – Incorrect, as floor area does not automatically allow for increased storage unless fire protection systems are in place.

Option D (the control area is provided with exhaust ventilation) – Incorrect, because ventilation is required for hazardous material control but does not impact storage limits like sprinklers do.

Reference Sources:

International Fire Code (IFC) 2021 – Section 5003.1.1 & Table 5003.1.1(1) (Control Area Storage Limits for Flammable Liquids)

NFPA 30: Flammable and Combustible Liquids Code (Sprinkler-Adjusted Storage Quantities)

ICC Fire Inspector II Study Guide (2021)

Thus, the correct and verified answer is: C. the building is protected with automatic sprinklers. ?

Clearance Requirement for Sprinkler Systems Over Flammable Liquid Storage

According to International Fire Code (IFC) 2021, Section 5004.6 and NFPA 30: Flammable and Combustible Liquids Code, Section 16.5.1, there must be a minimum of 18 inches of clearance between the top of flammable liquid storage and the deflector or discharge orifices of a sprinkler system.

This ensures unobstructed sprinkler discharge for effective fire suppression.

2. Why 18 Inches is the Correct Answer

The 18-inch clearance allows sprinklers to operate properly, ensuring water distribution is not blocked by stored materials.

NFPA 13 also mandates an 18-inch minimum clearance for standard storage applications with sprinklers.

3. Verification of Other Options

Option B (24 inches) – Incorrect, as the IFC and NFPA specify 18 inches as the minimum requirement.

Option C (30 inches) – Incorrect, as this exceeds the required minimum clearance.

Option D (36 inches) – Incorrect, as the IFC and NFPA do not require this much clearance.

Reference Sources:

International Fire Code (IFC) 2021 – Section 5004.6 (Sprinkler Clearance Over Flammable Liquid Storage)

NFPA 30: Flammable and Combustible Liquids Code – Section 16.5.1

NFPA 13: Standard for the Installation of Sprinkler Systems – Minimum Clearance Requirements

ICC Fire Inspector II Study Guide (2021)

Thus, the correct and verified answer is: A. 18 inches. ?