How to write a safety data sheet yourself — and when not to

The 16 sections, and what each one actually requires

Most of the document is transcription discipline: say what is true, cite where it came from, keep every section consistent with Section 2. The checklist below notes what each section needs and flags the three where DIY authors fail.

Section 1: Identification

Product name as sold, recommended use, and the responsible company with a working phone number. The failure mode is cosmetic: a name that does not match the label, so the sheet and the product cannot be matched in an audit.

Section 2: Hazards identification — DIY TRAP

The classification, the label elements, and the hazards not otherwise classified. This is where DIY sheets fail most: the classification must follow the GHS criteria class by class, and a missed hazard class makes every downstream section wrong. If a component's supplier sheet says Aquatic Toxicity Chronic 2, your finished mixture may inherit it above the thresholds — and 'not classified' must be justified, not defaulted.

Section 3: Composition / information on ingredients

Each hazardous component, its CAS number and its concentration or range. For the EU, the REACH registration number where one exists. Trade secrets have a specific disclosure procedure — 'proprietary' in a casual sense is not it.

Section 4: First-aid measures

Symptoms and treatment per route of exposure, consistent with the Section 2 classification. Copying boilerplate about effects the classification does not support is a defect, not caution.

Section 5: Fire-fighting measures

Suitable extinguishing media, specific hazards from the chemical, and protective equipment for firefighters. Follows from the physical hazards in Section 2.

Section 6: Accidental release measures

Personal precautions, containment and cleanup. For most small-business products this section is short and standard — but it must still match the hazard.

Section 7: Handling and storage

Precautions for safe handling, conditions for safe storage, including incompatibilities. Incompatibilities come from the chemistry, not from a template's defaults.

Section 8: Exposure controls / PPE — DIY TRAP

Occupational exposure limits (PELs in the US, limit values in the EU) and respiratory, hand, eye and skin protection. This is the second failure point: limits live on regulatory lists that change, and PPE must answer the hazards in Section 2 rather than 'gloves and goggles' verbatim.

Section 9: Physical and chemical properties

Appearance, odour, pH, melting and boiling points, flash point, solubility and so on. Values must be real — measured, or sourced from the supplier sheets and databases. Inventing a plausible number here is the defect auditors find first.

Section 10: Stability and reactivity

Reactivity, chemical stability, incompatible materials, decomposition products. Follows the chemistry of the components.

Section 11: Toxicological information

Health effects per route, consistent with the classification. Where data is absent, say what is absent rather than asserting safety.

Section 12: Ecological information

Aquatic and terrestrial toxicity, persistence, bioaccumulation. Required in the EU and GHS-aligned formats; recommended in the US format.

Section 13: Disposal considerations

Disposal of the product and its container: local disposal authority, and the waste-treatment route the classification implies. In the EU this points at the Waste Framework Directive and national law rather than a single rule, so say what is true without inventing a code.

Section 14: Transport information — DIY TRAP

UN number, proper shipping name, class, packing group. The third failure point: the transport entry comes from the dangerous-goods lists (49 CFR 172.101 in the US, the ADR/RID tables in the EU) and does not always match the GHS classification the way authors expect.

Section 15: Regulatory information

The safety, health and environmental regulations specific to the product — TSCA status in the US, REACH and CLP in the EU.

Section 16: Other information

Revision date, changes from the previous version, and the disclaimer that the sheet is a draft for review by a qualified EHS professional.

When writing it yourself is sensible

You know the product well, it is a single substance rather than a formulation, its data exists in the supplier sheet you already hold, and you sell into one jurisdiction. Then the job is careful transcription and classification — hours, not days — and doing it yourself keeps the knowledge in the company that owns the product.

When it is not — including when not to buy from us

A mixture with several hazardous components. A classification that turns on a threshold or a summation rule. An export market with its own language and its own implementation. And above all: a novel formulation with no public record, where the classification needs read-across justification from analogous substances — that is skilled regulatory work, and nobody should pretend otherwise.

We say this plainly because it bounds our own product. A machine-drafted document is generated from public regulatory data; for a novel compound there is no public record to draft from, so the $5 path refuses rather than guess — and the honest recommendation for that case is a human consultant, not our Pro tier ($99/month, draft R&D sheet with read-across disclosure) either. Where the middle path does fit: our machine draft as the first working copy, which you review against your own data — the lookup half done in minutes, your judgement on the rest.

The GHS safety data sheet guide covers the classification criteria in depth, and the mixture calculator computes the Annex I summation rules for a declared formula, free.