Walk into most Indian commercial buildings and you will find the same thing: ABC dry powder extinguishers, evenly spaced, ticking a box. It is the default because it is cheap, versatile and passes a casual inspection.
It is also, in specific and predictable places, the wrong choice — and in those places the wrong extinguisher is genuinely worse than no extinguisher at all. Someone will pick it up, use it, make the situation worse, and lose the thirty seconds in which the fire was still small.
Fire Classes First
You cannot choose an extinguisher without naming the fire. Indian practice classifies fires as:
- Class A — ordinary combustibles: wood, paper, cloth, rubber, most plastics
- Class B — flammable liquids: petrol, diesel, solvents, thinners, paints
- Class C — flammable gases: LPG, acetylene, methane
- Class D — combustible metals: magnesium, sodium, aluminium swarf
- Class F / K — cooking oils and fats
- Electrical fires — not a separate class but a condition: the risk is conductivity, so the agent must not conduct
The rest of this article is really just matching agents to that list.
ABC Dry Powder
What it does. Mono-ammonium phosphate powder interrupts the chemical chain reaction and blankets the fuel. Effective on A, B and C.
Why it dominates. One extinguisher covers three classes at low cost. For a general office, corridor, factory floor or godown, it is the sensible default.
What it costs you. Powder goes everywhere and it is corrosive to electronics. Discharging one in a server room means the servers are finished even if the fire was not. Cleanup after a discharge in a working area is significant, and the powder gets into machinery, ducts and bearings.
Where to use it. General areas, corridors, factory floors, warehouses, car parks, LPG storage areas.
Where not to. Server rooms, control rooms, laboratories, clean environments, commercial kitchens, and anywhere a discharge would cost more than the fire.
Carbon Dioxide (CO₂)
What it does. Displaces oxygen and cools. Leaves no residue whatsoever.
Why it matters. For live electrical equipment, this is the right answer. Nothing to clean up, nothing conductive, nothing corrosive. The equipment that survives the fire also survives the extinguisher.
Limitations worth knowing.
- Almost useless on Class A deep-seated fires — it knocks down flame but does not cool the fuel bed, so it re-ignites
- No post-discharge protection, unlike foam or powder
- The horn gets extremely cold; untrained users injure their hands
- Asphyxiation risk in small, unventilated rooms. This is the one that gets underestimated. In a tight electrical cupboard or a small server room, a large CO₂ discharge is a genuine hazard to the person holding it.
Where to use it. Electrical panel rooms, server and network rooms, laboratories, plant rooms, workshops with live equipment.
Mechanical Foam (AFFF)
What it does. Forms a film over the surface of a burning liquid, cutting off vapour and preventing re-ignition. Works on Class A as well.
Why it matters. For flammable liquid risk, foam is the correct answer, and the sealing action is the point — powder knocks the flame down but the vapour is still there and the pool can re-light. Foam suppresses the vapour.
Limitations. Conductive, so not for live electrical equipment. And standard AFFF will break down on polar solvents — alcohols, ketones, esters — because the solvent absorbs the water in the foam. For those fuels you need alcohol-resistant AR-AFFF, not ordinary AFFF. Getting this wrong in a chemical or pharmaceutical plant is a serious specification error.
Where to use it. Fuel storage and dispensing, generator rooms, paint and solvent stores, chemical handling, workshops, loading bays.
Clean Agent
What it does. Discharges a gaseous agent that suppresses fire without residue, without water, and without conductivity.
Why it matters. It is the combination of CO₂’s no-residue benefit with better Class A performance and a far lower asphyxiation concern at design concentration. For protecting high-value electronics where a person may need to use a portable unit in an occupied room, it is the best portable option available.
Limitations. The most expensive option per unit. Overkill for general areas.
Where to use it. Server rooms, data halls, control rooms, telecom equipment rooms, archives, museum stores, medical imaging rooms, aircraft and marine applications.
Water and Water Mist
Water is excellent on Class A and only Class A. Conductive, and dangerous on liquid fires — it spreads the burning fuel rather than extinguishing it.
Water mist portables are a genuinely underused option in India. The mist is fine enough to be non-conductive at a safe distance, works well on Class A, handles Class F cooking oils, and leaves negligible water damage. For hospitals, hotels, schools and heritage buildings they solve several problems at once.
Class F — Wet Chemical for Kitchens
Cooking oil at frying temperature is not a Class B fire and does not behave like one. It burns hotter, holds heat in the oil mass, and re-ignites after the flame is knocked down.
Do not put an ABC extinguisher next to a fryer. The powder blast can splash burning oil out of the pan. The correct portable is a wet chemical (Class F) unit, which saponifies the surface of the oil into a soapy layer that seals it and prevents re-ignition. Any commercial kitchen should also have a fixed hood suppression system — the portable is for what escapes it.
Quick Reference
| Area | Correct choice | Avoid |
|---|---|---|
| General office, corridor | ABC dry powder | — |
| Server / data room | Clean agent, or CO₂ | ABC powder |
| Electrical panel room | CO₂ or clean agent | Foam, water |
| Generator room | Foam + CO₂ | Water alone |
| Commercial kitchen | Wet chemical (Class F) | ABC powder |
| Paint / solvent store | AR-AFFF foam | Water |
| Chemical plant (polar solvents) | AR-AFFF foam | Standard AFFF |
| Warehouse, godown | ABC dry powder | — |
| Laboratory | CO₂ or clean agent | ABC powder |
| Hospital ward | Water mist or clean agent | ABC powder |
| LPG storage | ABC dry powder | Water, CO₂ |
| Car park | ABC dry powder or foam | — |
Quantity and Placement
Choosing the type is half the job. IS 2190 governs selection, provision and maintenance, and the principles are straightforward:
- Travel distance — nobody should walk far to reach an extinguisher. Around 15 m is a common design figure for Class A risk, shorter for Class B.
- Mount them where they are visible, at a height a person can lift the unit down from, with clear signage above so they are findable from across the room.
- Never block them. The most common real-world failure is a pallet, a filing cabinet or a parked scooter in front of the extinguisher.
- Rate them for the risk. A 1 kg unit in a factory is decorative. A 9 kg ABC or a 22.5 kg trolley unit belongs in an industrial area.
- Maintain them. Monthly visual check, annual service, hydrostatic testing at prescribed intervals. An extinguisher with a discharged gauge is a compliance failure and a safety failure.
Two Specification Checks
Insist on the ISI mark. Extinguishers should conform to IS 15683 and carry the ISI mark. Unmarked units will be queried at inspection and may not perform as rated.
Ask about TAC approval. For industrial and commercial property, TAC-approved equipment affects insurance rating and claim admissibility. It is worth confirming before you buy, not after a loss.
Where We Fit
Unitor India supplies the full UNITOR extinguisher range — ABC dry powder, CO₂, mechanical foam, water, water mist and clean agent, from 1 kg portables to 75 kg trolley units, ISI marked to IS 15683 — along with brackets, stands, signage, refilling and annual servicing.
Send us a floor plan and a note on what happens in each area and we will mark up the correct type, size and quantity rather than quoting a uniform grid of ABC units. Call +91 96002 09001 or email info@unitors.in.