Sheet 19Domain 4 of 5 · Emergency Preparedness and Management
100 feet to an extinguisher: STSC fire prevention under 1926.150
Under 29 CFR 1926.150(c)(1)(i), a building under construction needs a 2A-rated extinguisher for every 3,000 square feet, and no point on the floor may be more than 100 feet of travel from the nearest one. General industry uses 75 feet, so 100 is the construction figure to carry onto a site. This sheet covers placement, extinguisher classes, flammable-liquid storage and the point where a worker stops fighting a fire.
Construction fire rules from 29 CFR 1926.150 to 1926.152scroll →
Requirement
Construction figure
Section
Travel distance to the nearest 2A unit
100 ft or less from any point of the protected area
1926.150(c)(1)(i)
Extinguisher coverage on a building floor
One 2A unit per 3,000 sq ft, and at least one on each floor
1926.150(c)(1)
Multistory buildings
At least one extinguisher next to a stairway
1926.150(c)(1)
Flammable liquid or gas in use
A 10B unit within 50 ft where more than 5 gal of liquid or 5 lb of gas is in use
1926.150(c)(1)
Banned extinguishers
Carbon tetrachloride and other toxic vaporizing-liquid types
1926.150(c)(1)
Storage cabinets
Up to 60 gal of Category 1–3 or 120 gal of Category 4 liquid per cabinet, and no more than 3 cabinets in one storage area
1926.152
Inside storage room
A 20-B unit outside the door, within 10 ft of it
1926.152
Outdoor container storage
Up to 1,100 gal per pile, 20 ft from any building, with a 20-B unit 25–75 ft away
1926.152
Fueling equipment
A 20-B:C unit within 75 ft of each pump, and engines off while fueling
1926.152
Categories 1–4 are the GHS flammable-liquid categories used by hazard communication and by 29 CFR 1926.152. Inspection, cylinder storage and the remaining storage limits come up in the cards below.
Talking point 02
Fire scenes to work through
Panels, lumber yards, cylinder cages and open floors: the scenes mix what to grab when something is burning with what to fix before anything does.
Card 1 of 15 · 0 right
Card 1
A trained laborer notices a small fire in a pile of cardboard packaging near a stair tower. An ABC extinguisher hangs 20 ft away, and the exit is clear. What should the laborer do FIRST?
Pick an answer. A short note for each option, A to D, appears here.
ACorrect: Workers should fight only incipient fires, and only after the alarm is raised, so help is coming if the fire grows.
BAn ABC unit covers ordinary combustibles like cardboard, and checking the rating should not delay the alarm.
CAttacking at once is tempting for a small fire, but if it grows, no one has been alerted.
DMoving combustibles can help later, but it delays the alarm and keeps the laborer close to the fire.
Card 2
During a walkthrough of an interior fit-out floor, a supervisor finds cardboard, wood offcuts, and oily rags piled near a running temporary heater. Which action BEST reduces the fire risk?
Pick an answer. A short note for each option, A to D, appears here.
AA watcher can react to a fire but does not remove the fuel next to the ignition source.
BA sign addresses smoking and open flames, but the hazard here is fuel piled near a running heater.
CCorrect: Removing fuel from near the ignition source eliminates the fire hazard, and good housekeeping keeps it from returning.
DAn extra extinguisher helps respond to a fire but does nothing to prevent one.
Card 3
During a site walk, a supervisor finds a portable extinguisher with a cracked pressure gauge and a torn hose. Under 29 CFR 1926.150, what must be done?
Pick an answer. A short note for each option, A to D, appears here.
AWaiting for the annual service leaves the area without a working extinguisher for months.
BMoving it removes a false sense of protection but still leaves the area without coverage.
CCorrect: 29 CFR 1926.150 requires firefighting equipment to be kept in operating condition and defective equipment to be replaced immediately.
DA defective unit cannot stay in service, and the monthly check is no reason to delay replacement.
Card 4
A superintendent plans to stack lumber in the open yard beside a building under construction. Which arrangement meets 29 CFR 1926.151?
Pick an answer. A short note for each option, A to D, appears here.
ACorrect: Outdoor combustible piles are limited to 20 ft in height and must be kept at least 10 ft from any building.
BStacking against the wall lets a yard fire spread into the building, whatever the pile height.
CThirty feet exceeds the 20 ft height limit, and 5 ft is too close to the building.
DThe height is within the limit, but 5 ft is half the required 10 ft separation from the building.
Card 5
What record shows that a portable fire extinguisher on site has received its required annual maintenance?
Pick an answer. A short note for each option, A to D, appears here.
AA purchase invoice shows when the unit was bought, not that it was maintained.
BCorrect: Annual maintenance is recorded on a tag or label showing the month, year and the person who did the work.
CMonthly initials record the quick visual inspection, not the annual maintenance.
DThe manufacturer's date stamp shows when the shell was made, not when it was last serviced.
Card 6
A crew stores full oxygen and acetylene cylinders together in one cage overnight. Under 29 CFR 1926.350, what storage arrangement is required?
Pick an answer. A short note for each option, A to D, appears here.
AClosed valves and caps do not prevent a leak from creating a dangerous oxygen and fuel-gas mixture in one cage.
BNeither 25 ft nor a 3-ft barrier matches the rule, which also requires the barrier to have a fire-resistance rating.
CCaps and upright chaining are required, but they do not replace separation, and 10 ft is too close.
DCorrect: Stored oxygen must be kept 20 ft from fuel-gas cylinders or separated by a noncombustible barrier at least 5 ft high with a half-hour fire rating.
Card 7
Which training method BEST prepares designated workers to use portable fire extinguishers on a real jobsite fire?
Pick an answer. A short note for each option, A to D, appears here.
AA written quiz checks knowledge of fire classes but does not build the hands-on skill to use an extinguisher.
BA video shows the steps but gives no practice handling a real extinguisher.
CCorrect: Hands-on practice on a controlled fire builds the skill and confidence workers need in a real emergency.
DWatching a demonstration beats a video but still gives workers no practice of their own.
Card 8
An excavator bucket snags and ruptures a natural gas service line, and gas is blowing from the trench. What should the supervisor do FIRST?
Pick an answer. A short note for each option, A to D, appears here.
AKeeping the crew near the escaping gas exposes them to fire or explosion if it ignites.
BCorrect: Escaping gas can ignite at any moment, so people are moved away, ignition sources removed, and 911 and the utility called.
CWorkers should not try to stop a pressurized gas leak; only the utility should handle it.
DBackfilling can push gas into nearby buildings or utility lines and does not stop the leak.
Card 9
A trained carpenter has raised the alarm and grabbed an ABC extinguisher. Smoke from a burning insulation pile is banking down from the ceiling and filling the corridor to the only exit. What should the carpenter do?
Pick an answer. A short note for each option, A to D, appears here.
AStaying low helps escape, but fighting the fire from there risks being cut off from the only exit.
BPASS is the right technique for a small fire, but this one is past the stage where workers should fight it.
CCorrect: Smoke filling the only exit route means the fire is beyond the incipient stage, so the carpenter must leave.
DAiming at the smoke wastes the agent and does nothing to control the fire.
Card 10
A contractor stores Category 1 flammable liquids inside a building under construction. How much may be kept in a room outside an approved flammable storage cabinet?
Pick an answer. A short note for each option, A to D, appears here.
AThe 120-gallon figure is a cabinet limit for Category 4 liquids, not the amount allowed in a room outside a cabinet.
BFive gallons is the amount that triggers a 10B extinguisher within 50 ft, not a storage limit.
CCorrect: The construction rule limits flammable liquids kept in a room outside an approved cabinet to 25 gallons.
DSixty gallons is the maximum for Category 1 to 3 liquids inside one approved cabinet.
Card 11
Following NFPA 10, which 29 CFR 1926.150 relies on for extinguisher maintenance, how often should portable extinguishers on a construction site get a quick visual inspection?
Pick an answer. A short note for each option, A to D, appears here.
AWeekly is the 1926.50 interval for checking first-aid kits, a common mix-up.
BAnnual is the more detailed maintenance by a trained technician, not the quick visual check.
CCorrect: NFPA 10 calls for a quick visual check about every 30 days to confirm the unit is in place, charged and undamaged.
DQuarterly is not an NFPA 10 interval for portable extinguisher inspection.
Card 12
What is the PASS technique used for?
Pick an answer. A short note for each option, A to D, appears here.
ACPR follows its own sequence of compressions and breaths, not PASS.
BCorrect: PASS stands for Pull, Aim, Squeeze, Sweep, the steps for using a portable extinguisher.
CSafety inspections rely on checklists and hazard walks, not the PASS steps.
DStructural stability is judged by a competent or qualified person, not with PASS.
Card 13
Which of the following would be classified as a Class A fire?
Pick an answer. A short note for each option, A to D, appears here.
ACorrect: Class A fires involve ordinary combustibles such as wood, paper and cloth.
BFires in energized electrical equipment are Class C.
CCombustible metals such as magnesium burn as Class D fires.
DFlammable liquids such as gasoline and solvents are Class B.
Card 14
A fire starts inside a temporary electrical panel feeding a job trailer, and the power cannot be safely shut off. Which extinguisher should a trained worker use?
Pick an answer. A short note for each option, A to D, appears here.
AClass D agents are for combustible metals such as magnesium, not electrical fires.
BWet chemical Class K units are meant for cooking oils and fats in kitchens.
CWater conducts electricity and can shock the user on energized equipment.
DCorrect: CO2 does not conduct electricity, so a unit with a C rating is safe to use on energized equipment.
Card 15
On a cold morning, laborers want to burn scrap lumber in a steel drum, a solid-fuel salamander, inside a partly enclosed building under construction to stay warm. What should the supervisor decide?
Pick an answer. A short note for each option, A to D, appears here.
AAn extinguisher helps if a fire spreads, but solid-fuel salamanders are banned in buildings whatever is kept beside them.
BA noncombustible base addresses one hazard. The open fire, its sparks and its carbon monoxide remain.
CCorrect: Solid-fuel salamanders are prohibited in buildings and on scaffolds, so heat comes from an approved heater with fresh air supplied.
DWatching the fire does nothing about the carbon monoxide and sparks, and the device is banned indoors anyway.
Talking point 03
Three kinds of fire card
Matching. A fuel is named and you pick the extinguisher class or the agent. The letter on the unit's label has to fit what is burning.
Figures. Coverage, distance and storage limits from Subpart F. A 30-minute fire watch in a hot-work option comes from general industry; the hot work and fire watch sheet has the construction rule.
Decisions. A fire, a trained worker, a short scene. Read every detail in the stem before you choose.
To work fire in with the other four domains, open the STSC practice test.
Talking point 04
A fire-prevention walk of one floor
Find what can light
Temporary heaters, torches and hot work, grinders, temporary wiring and panels, the smoking area. Note where each one is.
Look at what sits next to it
Note the foam board, packaging, form lumber, solvent cans and fuel within reach of each ignition source on your list.
Check the extinguishers
Count them against the floor area and pace the distance from the far corners. Each one in place, visible, charged and rated for the fuels on that floor, with nothing stacked in front of it.
Check storage and signs
Flammable liquids in safety cans or approved containers, cabinets within the limits in the table, and “No Smoking or Open Flame” signs posted where fuel is stored or handled.
Walk the way out
Stairs and corridors clear, and the alarm tested. The emergency action plans sheet covers routes, alarms and drills.