Fire-safety classification in the paint store shed
A Tradesman Mate in charge of a naval store shed holds the following stock in a single 12 m × 8 m shed with one door: 40 steel drums of enamel paint, 12 cans of thinner and turpentine, 6 LPG cylinders meant for the canteen, 4 carboys of sulphuric acid for battery topping-up, and a stack of wooden pallets and gunny bags. During a monsoon inspection the fire officer notes that the shed contains one 9-litre stored-pressure water-type extinguisher, a bucket of dry sand and no signage. Before signing the compliance certificate he asks three things: what class of fire each material represents, what extinguishing medium is appropriate for each, and whether this stock may continue to be held together in one shed. The Tradesman Mate must also explain what he would do in the first 60 seconds if a thinner can caught fire while he was working alone inside.
1. Classify each material by fire class and name the suitable extinguishing medium for each.
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| Material | Class (IS classification) | Suitable medium |
|---|---|---|
| Wooden pallets, gunny bags, paint-soaked rags | A - ordinary combustibles that leave ash | Water, foam, dry chemical powder (DCP) |
| Enamel paint, thinner, turpentine | B - flammable liquids | Foam, CO₂, DCP. Never a water jet - it spreads the burning liquid |
| LPG cylinders | C - flammable gases | DCP or CO₂; the first action is always to shut off the supply |
| Sulphuric acid | Not a fire class in itself - corrosive oxidiser | No extinguisher 'for acid'; keep it from organic matter and never apply water, which reacts violently and spatters |
| Shed lighting and wiring | Electrically energised equipment, usually treated as a separate class in Indian practice | Isolate the supply first, then CO₂ or DCP |
The single 9-litre water extinguisher covers only Class A. It is nearly useless - and potentially dangerous - on the paint, thinner and LPG, which are the bulk of the risk. Exact class lettering and medium choice should still be checked against the station fire order in force, since local instructions may add restrictions.
2. May all five categories continue to be stored in this one shed? Give your decision with reasons and the minimum changes you would demand.
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No. Four defects make a single shed unacceptable:
- LPG inside the shed - a gas release turns the shed into a fuel-air bomb, and the only door is between the cylinders and the occupants' escape route.
- Combustible packaging beside flammable liquids - pallets and gunny bags give the fire its first fuel and bridge the gap to the paint drums.
- Acid carboys beside steel drums - leakage corrodes the drums, and acid-plus-organic matter is an ignition source; there is no bunding to contain a spill.
- Wrong extinguisher and no signage - a Class A water extinguisher in a Class B/C store, and no 'No smoking - flammable' board.
Minimum changes: move the LPG to an outdoor ventilated cage at the distance laid down in station orders; shift thinners and turpentine to a separate ventilated flameproof compartment; keep acid on low pallets inside a drip tray away from metals; remove loose pallets and gunny bags from the shed; provide at least one 5 kg DCP and one CO₂ extinguisher near the exit, with signage and a sand bucket retained. Reduced quantities per compartment must be confirmed against the local fire order rather than assumed.
3. What should the Tradesman Mate do in the first 60 seconds if a thinner can ignites while he is alone inside the shed?
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Order of action - people first, then property, and never the wrong medium:
- Raise the alarm immediately - shout, and use the nearest call point or phone the quarter guard/fire brigade before touching anything. A fire fought silently is the classic fatal mistake.
- Do not throw water. Water on burning thinner spreads the fire and can push flaming liquid towards the drums.
- Isolate if it is safe, i.e. switch off the shed supply and shut the LPG cylinder valve only if the cylinder is away from the fire and the escape route stays clear. If either condition fails, leave it.
- Attack only a small fire, with the exit at your back, using CO₂ or DCP; keep low, aim at the base of the flames. If the fire is not knocked down in a few seconds, or the drums are being heated, abandon it.
- Evacuate, close the door behind you to limit air, move others upwind, account for personnel and report to the officer of the day.
Reporting afterwards is not optional: the fire officer needs the cause and the store ledger needs the loss entry.