The 16 sections of a safety data sheet, explained

Whether it is written for WHMIS in Canada, OSHA in the US or REACH in Europe, a modern safety data sheet follows the format set by the UN Globally Harmonized System (GHS): 16 sections, always in the same order. The headings are the same everywhere. What changes between markets is the detail each section must contain.

Sections 1 to 3: who, what and how hazardous

Section 1, Identification, names the product exactly as it appears on the label, gives its recommended use and restrictions on use, and the supplier's name, address and phone number, plus an emergency phone number. The supplier must be the one the market expects: in Canada, a Canadian manufacturer, importer or distributor; in the EU, a company established in the EU.

Section 2, Hazard identification, is the heart of the document: the classification, and the label elements that follow from it (pictograms, signal word, hazard and precautionary statements). It must match the label exactly, and it must follow from the data in sections 3, 9 and 11.

Section 3, Composition, lists the hazardous ingredients with their chemical names, CAS numbers and concentrations. Each market has its own rules on which ingredients must be listed and when a range can be given instead of an exact figure. In Canada and the US, a concentration withheld as confidential must be replaced by one of the prescribed concentration ranges.

Sections 4 to 6: emergency response

First-aid measures by route of exposure, fire-fighting advice and what to do after a spill. These sections are read by people dealing with an incident, so they need to be short, practical and consistent with the hazards in section 2.

Sections 7 and 8: handling, storage and protection

Section 7 covers safe handling and storage, including incompatible materials. Section 8 lists occupational exposure limits with their source, engineering controls and personal protective equipment. Exposure limits differ from one country to the next, and in Canada between provinces and territories, so section 8 is one of the sections that most often needs rework when an SDS moves between markets.

Sections 9 to 11: the technical data

Physical and chemical properties (section 9), stability and reactivity (section 10) and toxicological information (section 11). These are the evidence behind the classification: a flash point in section 9 should explain a flammable liquid classification in section 2, and a pH or an ingredient's toxicity should explain a corrosive or toxic one.

Sections 12 to 15: outside workplace law

Ecological information, disposal, transport and regulatory information are required headings in every market, but their status differs:

• Canada: the headings must be present, but the content is not mandatory under the Hazardous Products Regulations, because these topics fall under other laws.
• United States: OSHA requires the headings but does not enforce the content of sections 12 to 15, which are outside its jurisdiction.
• EU and GB: all four sections must be completed, with their subsections, as set out in Annex II of REACH and UK REACH.

Even where the content is optional, customers, carriers and waste contractors rely on it, so it is worth completing wherever the data allows.

Section 16: other information

The date of the latest revision, what changed, abbreviations and the sources used. In the EU and GB, changes made in a revision must be pointed out to recipients, usually in section 16.

Reviewing your own SDSs? Start here

1. Check section 2 against the label: the same pictograms, signal word and statements.
2. Check section 3 against your formula: every hazardous ingredient above its cut-off, with a CAS number.
3. Check that section 1 names the right supplier for the market.
4. Check the revision date in section 16, and whether the formula or the rules have changed since.

General information, not legal advice. Checked against the official sources above on 7 October 2026. Rules change: for your own products, ask for a spot-check.