How to read an industrial gas safety data sheet: the 16 GHS sections and the five that matter most for a gas

A safety data sheet is the one document every industrial gas cylinder should travel with, and the one most users file unread. For a gas it is also oddly structured: the format was designed for liquids and solids, so several sections that are full for a solvent are nearly empty for nitrogen, while the information that actually prevents accidents sits in four or five places. This guide walks through the 16 sections, explains which ones carry the weight for a gas, and shows how the sheet relates to the Indian rules that govern the cylinder.

The order is fixed by Annex 4 of the UN Globally Harmonized System (GHS), the same format that OSHA's Hazard Communication Standard, 29 CFR 1910.1200, adopts as Appendix D. Every compliant supplier puts the same information in the same place.

The five critical rows, Sections 2, 7, 9, 10 and 14, are the ones to read before the first cylinder is connected. The rest are for training, emergency planning and audit.

Section 2 tells you what kind of hazard the gas is. For industrial gases a small set of GHS hazard statements covers almost everything:

The most important thing Section 2 can say is often not a coded statement at all. GHS has no hazard class for simple asphyxiation, so nitrogen, argon and helium carry only the gas-cylinder pictogram and H280, and the caution that they displace oxygen without warning appears as text under "other hazards which do not result in classification". A sheet with one pictogram is not a safe-gas sheet; the nitrogen safety guide explains why an inert-gas atmosphere gives no warning.

Most of Section 9 is reference data, but one line, relative density, decides how a leak behaves and therefore where ventilation and detectors go.

Cold vapour from a liquid spill is denser than these figures while it is cold, so every cryogenic leak initially flows along the ground. Section 9 also carries the flammable range for fuel gases (acetylene 2.5 to 82 % in IS 14814:2023; hydrogen 4 to 75 %) and the vapour pressure for liquefied gases, which explains why a CO₂ or nitrous oxide cylinder gauge says nothing about its contents.

Section 7 is the operating instruction. For every gas it will say upright, secured, valve protected, shaded and ventilated; for oxidisers it adds no oil or grease and slow valve opening; for acetylene it adds the copper limit, the withdrawal rate and the requirement to stand a cylinder upright before use. Section 10 says what the gas reacts with. For most inert gases it is nearly empty. For acetylene it lists copper, silver and mercury (acetylide formation), oxidisers and the decomposition hazard; for oxygen and nitrous oxide, every combustible including lubricants; for nitrous oxide, its own exothermic decomposition. When Sections 7 and 10 disagree with local practice, the SDS is usually right and the practice is a habit.

Section 14 carries the identity that crosses borders and reaches the fire brigade. The UN numbers for the gases KIGL handles are fixed and, since the 2021 revision of IS 4379, are listed in Table 1 of IS 4379:2021:

IS 14814:2023 cl 4.2 gives acetylene's identity as UN 1001, Class 2.1, Hazchem code 2SE, and the cylinder colour, label and UN number should always agree with the sheet. A mismatch between the SDS and the cylinder is a reason to quarantine the cylinder.

KIGL publishes a full 16-section safety data sheet for each gas it supplies. The UN number and transport class below are taken from each sheet's Section 14.

1. Section 2: note every pictogram and H-statement, then read "other hazards" for the asphyxiant warning.
2. Section 9: note relative density and decide whether detection goes high, low or at breathing height.
3. Section 7: list the storage and handling rules and compare them with the store you have.
4. Section 10: list incompatible materials and check that none is in the store or in the fittings.
5. Section 14: write the UN number on the emergency plan, and check it against the cylinder label.

KIGL's full sheets are published under /sds/, starting with acetylene and oxygen, and each gas has an explainer: oxygen, nitrogen, argon, carbon dioxide and the others in this series. The explainer helps you understand the sheet; the sheet is what you keep at the point of use and hand to emergency services.