OSFM Fire Extinguisher 1 (FE1) Practice
Exam 2026 Practice Test –Question Study Guide
with Answers & Full Explanations | PDF.
Overview of the (OSFMFEI02)
The exam focuses on NFPA 10 (Standard for Portable Fire Extinguishers). Key
areas of testing include:
Classification of Fires (Class A, B, C, D, K).
Selection and Placement (Distance and Hazard requirements).
Inspection, Maintenance, and Recharging (Internal and external exams).
Hydrostatic Testing (Frequencies and safety procedures).
1. According to NFPA 10, a "Class K" fire involves which of the following materials?
A) Ordinary combustibles like wood and paper
B) Flammable liquids and gases
C) Combustible cooking media (vegetable or animal oils and fats)
D) Combustible metals like magnesium
Answer: C) Combustible cooking media
Rationale: Class K extinguishers are specifically designed for commercial kitchens
where high-temperature cooking oils require a "saponification" process to extinguish the
fire.
2. What is the maximum travel distance to a Class A fire extinguisher in a Light
Hazard occupancy?
A) 30 feet
B) 50 feet
C) 75 feet
D) 100 feet
Answer: C) 75 feet
Rationale: NFPA 10 specifies that for Class A hazards, the maximum travel distance
from any point to an extinguisher shall not exceed 75 feet (22.7 m).
,3. Fire extinguishers must be inspected visually at what minimum interval?
A) Daily
B) Weekly
C) Monthly
D) Annually
Answer: C) Monthly
Rationale: A "quick check" or visual inspection must be performed at least every 30
days to ensure the extinguisher is in its designated place, has not been tampered with,
and is fully charged.
4. Which of the following is an example of a "Class B" hazard?
A) Electrical transformers
B) Gasoline, oil, and paint thinners
C) Scrap titanium
D) Trash and rubber
Answer: B) Gasoline, oil, and paint thinners
Rationale: Class B fires involve flammable liquids, petroleum greases, tars, oils, oil-
based paints, solvents, lacquers, alcohols, and flammable gases.
5. When performing a hydrostatic test on a stored-pressure dry chemical
extinguisher with a stainless steel shell, what is the required interval?
A) 5 years
B) 12 years
C) 6 years
D) 10 years
Answer: B) 12 years
Rationale: While many extinguishers (like CO2 and Water) require a 5-year test, dry
chemical extinguishers with stainless steel or aluminum shells have a 12-year
hydrostatic test interval.
6. What is the purpose of the "siphon tube" in a portable fire extinguisher?
A) To mix the chemical with oxygen
B) To carry the extinguishing agent from the bottom of the tank to the valve
assembly
C) To act as a pressure relief valve
D) To hold the pull pin in place
Answer: B) To carry the extinguishing agent from the bottom of the tank to the
, valve assembly
Rationale: The siphon tube (or dip tube) ensures that the agent at the bottom is pushed
out by the pressurized gas at the top when the handle is squeezed.
7. A "Six-Year Internal Examination" is required for which type of extinguisher?
A) Carbon Dioxide (CO2)
B) Stored-pressure dry chemical
C) Non-rechargeable (disposable) halogenated agent
D) Distilled water
Answer: B) Stored-pressure dry chemical
Rationale: NFPA 10 requires that every 6 years, stored-pressure fire extinguishers that
require a 12-year hydrostatic test shall be emptied and subjected to the applicable
internal examination.
8. Which marking indicates an extinguisher is suitable for use on energized
electrical equipment?
A) The letter A in a green triangle
B) The letter B in a red square
C) The letter C in a blue circle
D) The letter K in a black hexagon
Answer: C) The letter C in a blue circle
Rationale: The "C" rating means the extinguishing agent is non-conductive and safe for
use on fires involving live electricity.
9. What must be replaced every time an extinguisher is recharged?
A) The entire valve assembly
B) The hose and nozzle
C) The discharge valve seat and "O" rings
D) The pressure gauge
Answer: C) The discharge valve seat and "O" rings
Rationale: To ensure a leak-proof seal after re-pressurizing, internal seals and O-rings
must be replaced during the recharging process.
10. Extinguishers having a gross weight not exceeding 40 lbs must be installed so
that the top of the extinguisher is not more than ____ above the floor.
A) 3 feet
B) 4 feet
C) 5 feet
, D) 6 feet
Answer: C) 5 feet
Rationale: NFPA 10 safety standards specify that extinguishers under 40 lbs should be
mounted no higher than 5 feet to ensure they are reachable for the average person.
11. What must be installed on the neck of a fire extinguisher after it has been
opened for internal maintenance?
A) A new pressure gauge
B) A "Verification of Service" collar
C) A plastic pull pin only
D) A manufacturer's warranty sticker
Answer: B) A "Verification of Service" collar
Rationale: NFPA 10 requires this collar to prove the extinguisher was actually
disassembled and serviced. It must contain the year and month of service and the
license number of the technician.
12. What is the hydrostatic test interval for a standard wet-chemical (Class K)
extinguisher?
A) 12 years
B) 5 years
C) 6 years
D) 10 years
Answer: B) 5 years
Rationale: Any extinguisher utilizing a liquid agent (Water, Foam, or Wet Chemical)
must be hydrostatically tested every 5 years due to the increased risk of internal
corrosion.
13. For Class B hazards, what is the maximum travel distance to an extinguisher for a
"High Hazard" area?
A) 75 feet
B) 50 feet
C) 30 feet
D) 100 feet
Answer: B) 50 feet
Rationale: Because flammable liquid fires spread rapidly, NFPA 10 requires shorter
Exam 2026 Practice Test –Question Study Guide
with Answers & Full Explanations | PDF.
Overview of the (OSFMFEI02)
The exam focuses on NFPA 10 (Standard for Portable Fire Extinguishers). Key
areas of testing include:
Classification of Fires (Class A, B, C, D, K).
Selection and Placement (Distance and Hazard requirements).
Inspection, Maintenance, and Recharging (Internal and external exams).
Hydrostatic Testing (Frequencies and safety procedures).
1. According to NFPA 10, a "Class K" fire involves which of the following materials?
A) Ordinary combustibles like wood and paper
B) Flammable liquids and gases
C) Combustible cooking media (vegetable or animal oils and fats)
D) Combustible metals like magnesium
Answer: C) Combustible cooking media
Rationale: Class K extinguishers are specifically designed for commercial kitchens
where high-temperature cooking oils require a "saponification" process to extinguish the
fire.
2. What is the maximum travel distance to a Class A fire extinguisher in a Light
Hazard occupancy?
A) 30 feet
B) 50 feet
C) 75 feet
D) 100 feet
Answer: C) 75 feet
Rationale: NFPA 10 specifies that for Class A hazards, the maximum travel distance
from any point to an extinguisher shall not exceed 75 feet (22.7 m).
,3. Fire extinguishers must be inspected visually at what minimum interval?
A) Daily
B) Weekly
C) Monthly
D) Annually
Answer: C) Monthly
Rationale: A "quick check" or visual inspection must be performed at least every 30
days to ensure the extinguisher is in its designated place, has not been tampered with,
and is fully charged.
4. Which of the following is an example of a "Class B" hazard?
A) Electrical transformers
B) Gasoline, oil, and paint thinners
C) Scrap titanium
D) Trash and rubber
Answer: B) Gasoline, oil, and paint thinners
Rationale: Class B fires involve flammable liquids, petroleum greases, tars, oils, oil-
based paints, solvents, lacquers, alcohols, and flammable gases.
5. When performing a hydrostatic test on a stored-pressure dry chemical
extinguisher with a stainless steel shell, what is the required interval?
A) 5 years
B) 12 years
C) 6 years
D) 10 years
Answer: B) 12 years
Rationale: While many extinguishers (like CO2 and Water) require a 5-year test, dry
chemical extinguishers with stainless steel or aluminum shells have a 12-year
hydrostatic test interval.
6. What is the purpose of the "siphon tube" in a portable fire extinguisher?
A) To mix the chemical with oxygen
B) To carry the extinguishing agent from the bottom of the tank to the valve
assembly
C) To act as a pressure relief valve
D) To hold the pull pin in place
Answer: B) To carry the extinguishing agent from the bottom of the tank to the
, valve assembly
Rationale: The siphon tube (or dip tube) ensures that the agent at the bottom is pushed
out by the pressurized gas at the top when the handle is squeezed.
7. A "Six-Year Internal Examination" is required for which type of extinguisher?
A) Carbon Dioxide (CO2)
B) Stored-pressure dry chemical
C) Non-rechargeable (disposable) halogenated agent
D) Distilled water
Answer: B) Stored-pressure dry chemical
Rationale: NFPA 10 requires that every 6 years, stored-pressure fire extinguishers that
require a 12-year hydrostatic test shall be emptied and subjected to the applicable
internal examination.
8. Which marking indicates an extinguisher is suitable for use on energized
electrical equipment?
A) The letter A in a green triangle
B) The letter B in a red square
C) The letter C in a blue circle
D) The letter K in a black hexagon
Answer: C) The letter C in a blue circle
Rationale: The "C" rating means the extinguishing agent is non-conductive and safe for
use on fires involving live electricity.
9. What must be replaced every time an extinguisher is recharged?
A) The entire valve assembly
B) The hose and nozzle
C) The discharge valve seat and "O" rings
D) The pressure gauge
Answer: C) The discharge valve seat and "O" rings
Rationale: To ensure a leak-proof seal after re-pressurizing, internal seals and O-rings
must be replaced during the recharging process.
10. Extinguishers having a gross weight not exceeding 40 lbs must be installed so
that the top of the extinguisher is not more than ____ above the floor.
A) 3 feet
B) 4 feet
C) 5 feet
, D) 6 feet
Answer: C) 5 feet
Rationale: NFPA 10 safety standards specify that extinguishers under 40 lbs should be
mounted no higher than 5 feet to ensure they are reachable for the average person.
11. What must be installed on the neck of a fire extinguisher after it has been
opened for internal maintenance?
A) A new pressure gauge
B) A "Verification of Service" collar
C) A plastic pull pin only
D) A manufacturer's warranty sticker
Answer: B) A "Verification of Service" collar
Rationale: NFPA 10 requires this collar to prove the extinguisher was actually
disassembled and serviced. It must contain the year and month of service and the
license number of the technician.
12. What is the hydrostatic test interval for a standard wet-chemical (Class K)
extinguisher?
A) 12 years
B) 5 years
C) 6 years
D) 10 years
Answer: B) 5 years
Rationale: Any extinguisher utilizing a liquid agent (Water, Foam, or Wet Chemical)
must be hydrostatically tested every 5 years due to the increased risk of internal
corrosion.
13. For Class B hazards, what is the maximum travel distance to an extinguisher for a
"High Hazard" area?
A) 75 feet
B) 50 feet
C) 30 feet
D) 100 feet
Answer: B) 50 feet
Rationale: Because flammable liquid fires spread rapidly, NFPA 10 requires shorter
