Type “Class C fire extinguisher” into Google and you get two different answers, because the letter means two different things. In India, and on every ISI label, Class C is a fire in a flammable gas: LPG, PNG, CNG, acetylene. In the United States, Class C is an electrical fire. Most Indian buyers who search for one have read an American page and are actually looking for something to keep next to a panel or server. If that is you, go to our electrical fire extinguisher guide. If you have a gas cylinder, a gas bank or a burner, keep reading.
This guide covers what a Class C fire is under IS 2190, the one rule that matters more than any extinguisher when gas is burning, which extinguishers carry a C rating, and what a kitchen, hotel, hostel, lab or factory with a gas line should keep on hand.
Class C in India means gas
IS 2190, the Indian standard that fire officers use when they check a building, splits fires into five classes by what is burning: A solids, B liquids, C gases, D metals, F cooking oil. Electrical equipment is not a class; instead, each extinguisher is marked as safe or not safe for use on live equipment. The same lettering is used across Europe and most of Asia.
The American NFPA 10 system has no gas class. It uses A, B, C (electrical), D and K (kitchen). Because so much of what is written online about extinguishers comes from the US, the two systems get mixed up constantly, including on some Indian dealer websites. The label on the cylinder settles it: an Indian ISI label with a “C” pictogram shows a gas flame, not a plug.
Typical Class C risks in India:
- Domestic and commercial LPG cylinders, the 14.2 kg red cylinder and the 19 kg blue one
- Piped natural gas (PNG) in kitchens and societies, CNG in vehicles and filling stations
- Gas banks and manifolds behind hotels, hostels, canteens and cloud kitchens
- Acetylene and oxygen in welding shops, hydrogen and other lab gases
- Butane canisters, camping stoves, gas-fired boilers and ovens
The one rule for gas fires: stop the gas before the flame
This is the part that is different from every other class. A gas fire is a leak that has caught light. The flame is the leak burning itself off. If you put the flame out but the gas keeps flowing, you now have an invisible, spreading cloud of gas looking for the next spark, and when it finds one you get an explosion instead of a fire. Fire services teach the order as: shut the valve, then put out what is still burning.
What that looks like in practice:
- Turn off the regulator or valve if you can reach it without going through the flame. On a domestic cylinder, turn the regulator knob to off; on a gas bank, close the cylinder valves and the manifold isolation valve. If the flame is at the cylinder valve itself, a thick wet towel or gunny bag thrown over it usually smothers it long enough to close the valve.
- Only then use the extinguisher on whatever is still burning around it: curtains, a plastic bin, a cupboard.
- If you cannot stop the gas, leave. Get everyone out, close the door behind you, and call the fire brigade (101 / 112) and the LPG emergency line (1906). A gas fire that keeps burning at the source is safer than one you have extinguished without closing the valve.
- Never switch anything on or off in a room that smells of gas. A light switch, a fan regulator or a doorbell can be the spark. Open the windows, leave, and close the gas supply from outside if possible.
Extinguishers rated for Class C
ABC dry powder: the standard Class C extinguisher
Mono ammonium phosphate powder works on a gas flame by breaking the chemical chain reaction in the flame itself, which is exactly what a gas fire needs because there is no surface to cool or smother. Every ABC extinguisher sold with an ISI mark carries a C rating, and a 4 kg or 6 kg unit will put out a jet of burning LPG at a cylinder valve in a couple of seconds. It is also rated for A and B, so one unit covers a kitchen’s gas line, its wooden cabinets and its cooking spills. The older BC powder (sodium bicarbonate) is also rated for gas, but ABC has replaced it almost everywhere because it covers solids too.
Clean agent: Class C with no powder cleanup
A clean agent extinguisher is rated A, B and C and leaves no residue, so it is the choice for a laboratory with gas lines and expensive instruments, or a gas-fired boiler room with a control panel. It costs more per kilo than powder, which is why it is not the default for a hostel kitchen.
What is not rated for gas, and why
- CO2 can blow a small gas flame out, but the gas keeps flowing and relights from any hot surface. CO2 units are rated B and electrical, not C. Keep them for the panel, not the cylinder.
- Water and foam do nothing to a gas flame and will spread any burning liquid near it. Water does have one real use at a gas fire: a hose or bucket on a cylinder that is being heated by a nearby fire keeps it cool and stops the pressure building. That is a job for the fire brigade, not an extinguisher.
- Wet chemical (K-type) is for cooking oil. A commercial kitchen needs both: the K-type for the fryer and ABC powder for the gas bank and everything else.
What to keep where
- Home kitchen with an LPG cylinder: a 2 kg ABC unit mounted at the kitchen door (not next to the stove, where the fire will be) and a fire blanket. Check the rubber tube and regulator every six months; most domestic LPG fires start at a perished tube.
- Restaurant, hotel or canteen kitchen: a 6 kg ABC at each exit, a K-type at the cooking line, and a 6 kg or 9 kg ABC at the gas bank outside. Fire NOC inspectors in most cities now ask for a gas leak detector and an automatic shut-off valve on commercial LPG banks as well.
- Hostel, mess or cloud kitchen: same as a restaurant, plus a ceiling-mounted modular unit above the gas bank if it sits in an enclosed room, so a fire after hours gets knocked down before anyone arrives.
- Welding or fabrication shop: 6 kg ABC within reach of every welding bay, flashback arrestors on the torch lines, and cylinders chained upright, away from the bay.
- Lab with gas lines: clean agent 4 kg or 6 kg at the door, with the main gas isolation valve clearly labelled outside the lab.
- Society with PNG: the gas company handles the main line; the society’s job is an ABC unit on each floor and in the meter room, and making sure residents know where the isolation valve on their own line is.
Mount every unit on the way out of the room, not deep inside it, with the top of the handle no higher than 1.5 metres. The IS 2190 travel distance for ordinary risks is 15 metres; in a kitchen you want it closer than that. A 15-minute drill on closing the gas valve does more for safety than a second extinguisher, which is why we run free fire-safety training for every society and business that buys from us.
A note on CNG and LPG vehicles
A CNG car or auto fire is a Class C fire on wheels. The 1 kg or 2 kg ABC unit sold as a car fire extinguisher is rated for it. If the vehicle is on fire and the gas is venting, the right action is distance, not a second attempt: CNG cylinders have a pressure relief that vents with a loud roar, and the safe place is 30 metres away, upwind.
Frequently asked questions
What is a Class C fire in India?
Under IS 2190, Class C is a fire in a flammable gas such as LPG, PNG, CNG, butane, acetylene or hydrogen. It is not an electrical fire; that is the American NFPA meaning of Class C.
Which fire extinguisher is used for Class C fire?
ABC dry powder is the standard choice, and clean agent where residue matters. Both carry a C rating on an ISI label. CO2, water and foam are not rated for gas fires.
Which extinguisher is used for an LPG cylinder fire?
First close the regulator or valve; a wet towel over a valve flame helps you reach it. Then use an ABC dry powder extinguisher on anything still burning. If the valve cannot be closed, leave the room, call 101 or 112 and the LPG helpline 1906, and let the gas burn rather than put out the flame and leave a gas cloud.
Is a Class C fire extinguisher the same as an electrical fire extinguisher?
Only in the US. In India an “electrical” extinguisher is any unit marked safe for live equipment, usually CO2 or clean agent, and ABC powder qualifies too. A Class C rating on an Indian label is about gas.
What is the difference between Class B and Class C fires?
Class B is a flammable liquid (petrol, diesel, paint, oil), which you fight by sealing or smothering the surface. Class C is a gas, which has no surface, so you stop the flow first and use a powder that breaks the flame’s chain reaction. Our Class B guide covers liquids in detail.
Does an ABC extinguisher work on all three classes?
Yes. ABC stands for the three classes it is rated for: A solids, B liquids, C gases. It is also marked safe on electrical equipment up to the voltage stated on the label. It is not rated for Class D metal fires or Class F cooking oil.
Standards referenced: IS 2190 and IS 15683 from the Bureau of Indian Standards. LPG handling guidance is from the oil companies’ safety material; the all-India LPG emergency helpline is 1906.
Not sure what size you need for a gas bank or a kitchen? Send us a photo on WhatsApp and we will tell you, or see the full guide to fire extinguisher types for all seven types and what each is for.