How to write a safety data sheet that passes review

The content and order of a safety data sheet is set out in REACH Annex II, retained in UK law, and explained in detail in HSE's L130 guidance. Every SDS follows the same sixteen headings, in the same order, whatever the product:

1. 11. Identification of the substance or mixture, and of the company or undertaking.
2. 22. Hazards identification the classification, and the label elements that must match what actually appears on the product.
3. 33. Composition/information on ingredients concentration ranges for hazardous components, kept consistent with what is actually in the formulation.
4. 44. First aid measures by route of exposure.
5. 55. Firefighting measures extinguishing media and specific hazards arising from the substance.
6. 66. Accidental release measures spill response, containment and clean-up.
7. 77. Handling and storage including incompatibilities.
8. 88. Exposure controls/personal protection occupational exposure limits and the PPE they justify.
9. 99. Physical and chemical properties the data profile of the substance or mixture.
10. 1010. Stability and reactivity conditions and materials to avoid.
11. 1111. Toxicological information the health-effects data behind the classification.
12. 1212. Ecological information the environmental-effects data.
13. 1313. Disposal considerations waste handling.
14. 1414. Transport information the current dangerous goods classification for the transport mode in use.
15. 1515. Regulatory information the specific regulatory status of the substance or mixture in the market it is being supplied into.
16. 1616. Other information including the revision history, which is where version drift usually surfaces first.

Getting this list right is a template problem. Keeping every section consistent with the others, and with the physical label, is the actual work, and it is where the next two sections focus.

A safety data sheet supplied into Great Britain has to reflect the GB CLP classification, not the EU one. The two regimes started from the same base and can now diverge, in the same way UK REACH and EU REACH have diverged. The most common version of this error is reusing an EU-facing SDS, or EU-facing wording within Section 15, for a GB customer without checking whether the classification and regulatory references still hold under GB CLP. If you supply both markets, the safe approach is to treat GB and EU as two documents to maintain, not one document with a find-and-replace.

None of the following is exotic. They are the ordinary, recurring ways an SDS fails a review, in roughly the order a careful reviewer tends to find them:

• Section 2 does not match the label. The classification and label elements in the SDS have to be the same classification and elements printed on the physical product. A mismatch is one of the fastest ways to fail a customer or auditor review.
• Section 3 concentration ranges do not reflect the actual formulation. A range copied from an old version, or from a similar product, rather than the current composition.
• Section 8 exposure limits are out of date. Occupational exposure limits change. An SDS carrying a superseded limit is a common, avoidable finding.
• Section 14 has not been checked against the current transport rules. Dangerous goods classifications are revised periodically, and a transport section frozen at the last major update is a recurring gap.
• Section 15 mixes up GB and EU regulatory status. A GB safety data sheet has to reference GB CLP, not the EU regulation, and the two can now diverge. Reusing EU wording without checking it against the GB position is one of the more common post-Brexit errors.
• The UFI on the label and the composition in Section 3 do not line up. The Unique Formula Identifier is tied to a specific composition, so a reformulation that changes Section 3 without updating the UFI creates an inconsistency a reviewer will catch.

An extended safety data sheet, or eSDS, is the same sixteen-section document with exposure scenarios attached as an annex. It applies where a chemical safety report has been carried out for the substance, which under REACH generally follows from registering the substance above the tonnage threshold that triggers a chemical safety assessment, where the substance is classified as hazardous or meets the PBT or vPvB criteria. See ECHA's guidance on safety data sheets and exposure scenarios for the current detail. If you are not sure whether a product you supply needs an extended SDS, that is a registration-status question worth confirming directly rather than inferring from the product type.

Writing an SDS that passes review once is a different problem from keeping it accurate as the product, the regulation, or the classification changes underneath it. That is the subject of our companion article on SDS version control, which covers what triggers a revision and why the drift is usually silent until an audit finds it. The two problems share a root cause: an SDS is only as reliable as the composition and classification data it is drawn from at the moment it is generated.

Most chemical businesses land on one of three approaches, and the right one depends on your product range rather than your headcount. A small, stable range is often best served by a competent person authoring directly. A large or fast-changing range makes the manual cross-checking above expensive to repeat by hand for every product, every time a component changes. That is where a grounded drafting system, one that pulls Section 2, 3, 8 and 15 from the same verified source and flags an inconsistency before a human sees the draft, earns its keep, as covered in our article on AI for regulatory affairs. Whichever route you choose, the same rule applies: the system drafts, a named competent person reviews and approves, and nothing goes out under your company's name without that step.

• HSE — L130: The compilation of safety data sheets
• ECHA — Guidance on the compilation of safety data sheets
• ECHA — Safety data sheets and exposure scenarios

This is practical guidance, not legal advice.