5.3 Fire prevention in a building full of cardboard

1 The fire prevention plan, element by element

1910.39(a) triggers the same way the emergency action plan does — required when another standard in part 1910 requires one — and (b) requires it in writing, kept in the workplace, available for review, with the same oral option for employers with 10 or fewer employees. (c) lists five elements:

And 1910.39(d): the employer must inform employees, on initial assignment, of the fire hazards they are exposed to, and must review with each employee the parts of the plan necessary for self-protection.

2 The fuel load you created by shipping things

1910.176(c) — from Part 3 — requires storage areas to be kept free from accumulation of materials constituting hazards from tripping, fire, explosion or pest harborage. In a warehouse the accumulation is usually one of four things, and all four are byproducts of normal work.

• Idle wood pallets. The highest-consequence storage decision most buildings make. Fire codes limit indoor idle pallet storage tightly; the practical answer is outdoors, away from the building, in limited stacks, and a designated indoor area only where it cannot be avoided.
• Cardboard and film. Baled or binned on a schedule, not piled behind a rack run until Friday.
• Empty plastic totes and foam. High heat release, easy to ignore because they look clean.
• Dust and lint on equipment. 1910.178(q)(10) requires industrial trucks to be kept clean and free of lint, excess oil and grease — the same principle applies to motors, heaters and charger cabinets under 1910.39(c)(3).

3 Ignition sources, one by one

Fuel is unavoidable in a warehouse; ignition is not. Five sources cover nearly all warehouse fires, and each has a specific control in the standards.

1. 1
   Battery charging. 1910.178(g): charging in designated areas, ventilation to disperse fumes from gassing batteries, protection of the charging apparatus from trucks, no smoking in the charging area — (g)(10) — and precautions against open flames, sparks and electric arcs — (g)(11).
2. 2
   Propane. 1910.110(e)(13): LP-gas trucks may be used inside buildings, no more than two containers on a truck for motor fuel, and trucks must not be parked and left unattended in areas of possible excessive heat or sources of ignition. Container storage awaiting use follows 1910.110(f) — valves closed and protected, not near exits or stairways.
3. 3
   Hot work. Any cutting, welding, grinding or brazing in a building full of cardboard needs a permit system, a cleared and protected area, and a fire watch. The hot work permit and fire watch tools on this site cover the mechanics.
4. 4
   Electrical. Damaged cords on shrink-wrap machines and battery chargers, overloaded temporary power, extension cords used as permanent wiring, and covered or blocked electrical panels.
5. 5
   Heat-producing equipment. Unit heaters and portable heaters with combustibles stacked inside their clearance, compressors, and forklift exhaust against packaging. 1910.39(c)(3) is exactly this.

4 Flammable liquids and aerosols

Most warehouses hold more flammable liquid than they think: parts cleaner, aerosols, paint, adhesives, propane cylinders, lubricants, sanitizer. The governing standard is 1910.106 for flammable liquids, and the practical warehouse rules that come out of it are simple to state: keep quantities in general work areas small, put the rest in an approved storage cabinet or a proper storage room, keep containers closed, bond and ground when dispensing, and never store flammables near an exit, a stairway or a heat source.

Aerosols are worth naming separately because they are stored by the case in retail-facing distribution centers and they behave very differently in a fire — they rocket, and they spread burning liquid. Fire codes treat aerosol storage as a distinct commodity class with its own protection requirements. If your building stores pallet loads of aerosols, that is a sprinkler design question for the fire protection engineer, not a housekeeping one.

5 Keeping the protection systems working

The fire protection in a warehouse is mostly automatic, which means the only way it fails is quietly. 1910.37(a)(4) requires safeguards designed to protect employees during an emergency — sprinkler systems, alarm systems, fire doors, exit lighting — to be in proper working order at all times. Four things routinely put a warehouse sprinkler system out of the condition it was designed for:

• Storage into the spray pattern. 1910.159(c)(10) sets an 18-inch minimum vertical clearance between sprinklers and material below, for systems installed to meet an OSHA standard; the same figure is the working rule everywhere.
• Blocked control valves. A pallet in front of the riser or the valve room is a delay in a fire.
• Hangers, mains and heads struck by forklifts. A raised mast and a sprinkler main is a common and expensive collision — 1910.176(e) clearance signs exist for this.
• Impairments nobody tracked. A system valved off for a repair and left that way over a weekend. Every impairment needs a written tag, a responsible name and a restoration check.

6 Smoking, contractors and the small stuff

Two of the most common warehouse fire causes are cultural rather than technical. Smoking areas that drift closer to the building over time, and contractors working in the building under nobody's plan. 1910.178(g)(10) bans smoking in charging areas outright; the rest is your own designated-area rule, and it only holds if there is a legitimate place to go.

For contractors, the pattern that works is one page at induction: what the alarm sounds like, where the exits are, that hot work needs your permit, where they may and may not store materials, and who they call. It takes five minutes and it is the difference between a contractor's grinder in an aisle full of cardboard being a controlled activity and being the start of a total loss.