Gas cylinders are safe when they're handled with care, and most accidents come from a few avoidable mistakes: the wrong gas connected, a cylinder falling over, oil on an oxygen fitting. This guide covers the colour codes used in India and 12 rules we recommend to every customer, from welding shops to hospitals to families using oxygen at home.
Colour codes for common gases in India
In India, industrial gas cylinders are colour-coded under IS 4379 and medical gas cylinders under IS 3933. The usual colours for common gases:
| Gas | Typical cylinder colour |
|---|---|
| Oxygen (industrial) | Black |
| Medical oxygen | Black body with white top (shoulder) |
| DA (dissolved acetylene) | Maroon |
| Nitrogen | French grey with black neck |
| Argon | Peacock blue |
| Carbon dioxide (industrial) | Black with white band |
| Nitrous oxide | Blue (French blue) |
| Helium | Brown |
| Air | French grey |
Important: colour is only a guide. Paint fades, cylinders get repainted and mixed gases have their own markings. Always read the gas name stencilled on the cylinder and the label before connecting anything. If a cylinder has no readable name, don't use it. Return it to your supplier.
Cylinders in India are filled, tested and stored under the Gas Cylinders Rules, 2016, administered by PESO (Petroleum and Explosives Safety Organisation).
12 safety rules for handling gas cylinders
1. Identify the gas before you use it
Read the stencil and label, not just the colour. Connecting the wrong gas is one of the most dangerous mistakes, especially in hospitals.
2. Keep cylinders upright and secured
Chain or strap cylinders to a wall, stand or trolley. A falling cylinder can break its valve and turn into a projectile. DA cylinders must always be upright.
3. Transport them properly
Fit the valve cap, keep cylinders upright and tied in the vehicle, and never carry them inside a closed car cabin. Don't carry cylinders on two-wheelers.
4. Never roll, drag or drop a cylinder
Use a cylinder trolley. Don't lift a cylinder by its valve or cap.
5. Use the right regulator
Every gas has its own regulator and fittings. Never force a fitting or use an adaptor to connect a different gas.
6. No oil or grease on oxygen fittings
Oil and grease can ignite in contact with high-pressure oxygen. Keep oxygen valves, regulators and hoses clean and dry, and don't handle them with oily gloves.
7. Check for leaks with soapy water
Brush soapy water on joints and look for bubbles. Never check for leaks with a flame.
8. Open valves slowly
Open the cylinder valve slowly, standing to one side of the regulator rather than in front of the gauge face.
9. Close valves after use, and don't run cylinders completely empty
Close the cylinder valve whenever you stop work. Return cylinders with a little pressure left and the valve closed, so moisture and air don't get in.
10. Store cylinders in a safe place
Choose a shaded, dry, ventilated area away from heat, electrical panels and exits. Keep oxygen and other oxidisers apart from fuel gases like DA, and keep full and empty cylinders separate.
11. Never use a damaged cylinder
Don't use cylinders with dents, bulges, fire damage, corroded bases or damaged valves. Never repaint cylinders, change markings or try to transfer gas from one cylinder to another yourself.
12. Know what to do in an emergency
- Leak: if it's safe, close the valve. Open doors and windows, don't operate electrical switches, keep flames away and move people out.
- Fire: clear the area and call the fire service on 101. Don't try to move a hot DA cylinder.
- Medical emergency: call 108.
Extra care for medical oxygen at home
Keep the oxygen cylinder at least 2 metres away from gas stoves, diyas, agarbattis and anyone smoking, and don't use oil-based creams on the face while on oxygen. Our home oxygen guide covers this in detail.
Need help?
If you're unsure about a cylinder, a regulator or how to store gases at your workshop or hospital, call Parameswara Traders on 094400 79857 or visit us on Bellary Road, Kurnool. We've supplied industrial and medical gases here since 1992 and are happy to explain.