How to Write a GHS-Compliant Safety Data Sheet

Imperium SDS guides · 2026-08-23

A safety data sheet (SDS) is the standard document for communicating chemical hazards down the supply chain. Under the UN's Globally Harmonized System (GHS) — adopted in the United States as OSHA's Hazard Communication Standard (HazCom 2012), in Canada as WHMIS 2015, and in the EU under the CLP Regulation ((EC) No 1272/2008) together with REACH — every SDS follows the same 16-section format, in the same order, with the same headings. That consistency is the whole point: an emergency responder or industrial hygienist should be able to find the same information in the same place on any sheet, anywhere.

This guide walks through what belongs in each of the 16 sections, the mistakes that show up most often in real-world sheets, and where software-assisted authoring genuinely helps.

The 16 sections, in order

Section 1 — Identification

Product identifier (matching the label), recommended uses and restrictions, and the supplier's name, address, and phone number, plus an emergency contact. This section is more jurisdiction-sensitive than it looks: several jurisdictions expect an in-country supplier identity or specific emergency contact arrangements — an EU sheet, a Canadian sheet, and a US sheet for the same product often carry different Section 1 blocks. Requirements vary by jurisdiction, so verify the current rules for each market you ship into (see our guide to OSHA, WHMIS, and CLP differences).

Section 2 — Hazard identification

The GHS classification of the product as a whole: hazard classes and categories, signal word, hazard statements (H-codes), precautionary statements (P-codes), and pictograms. For a mixture, this classification must be derived — from test data on the mixture, bridging principles, or the GHS calculation rules applied to the ingredients — not copied from somewhere convenient. How that derivation works is its own topic; see GHS mixture classification, explained.

Section 3 — Composition / information on ingredients

Hazardous ingredients with their chemical identity (usually CAS number) and concentration or concentration range. Disclosure rules — which ingredients must be listed, whether ranges are acceptable, and how trade-secret claims work — differ by jurisdiction, so check the rules that apply to you. The composition listed here must be consistent with the classification in Section 2; a reviewer who can't reproduce Section 2 from Section 3 has found a problem.

Section 4 — First-aid measures

Instructions by route of exposure (inhalation, skin, eye, ingestion), the most important symptoms and effects, and any need for immediate medical attention. Write for a lay responder, not a physician.

Section 5 — Fire-fighting measures

Suitable (and unsuitable) extinguishing media, specific hazards arising from the chemical — including hazardous combustion products — and protective equipment and precautions for fire-fighters.

Section 6 — Accidental release measures

Personal precautions and emergency procedures, environmental precautions, and methods for containment and clean-up, scaled sensibly to small and large spills.

Section 7 — Handling and storage

Precautions for safe handling (ventilation, ignition-source control, hygiene practices) and conditions for safe storage, including incompatibilities. This section should agree with Section 10: don't warn about incompatible materials there and stay silent here.

Section 8 — Exposure controls / personal protection

Occupational exposure limits for the ingredients (OSHA PELs, ACGIH TLVs, NIOSH RELs, and — for EU or Canadian sheets — the applicable regional limits), engineering controls, and PPE recommendations. Exposure limits are ingredient-level data, published by different bodies with different values, and they change; this section goes stale quietly. We cover it in depth in SDS Section 8: exposure limits.

Section 9 — Physical and chemical properties

The standard property list: appearance, odor, pH, melting/freezing point, boiling point, flash point, flammability, vapor pressure, density, solubility, and so on. Report what is known; where a property is not available or not applicable, say so rather than leaving a blank. Properties here feed classification (flash point drives the flammable-liquid category, for example), so they must be consistent with Section 2.

Section 10 — Stability and reactivity

Reactivity, chemical stability, possibility of hazardous reactions, conditions to avoid, incompatible materials, and hazardous decomposition products.

Section 11 — Toxicological information

Health-effect information by exposure route: acute toxicity data (LD50/LC50 where available), irritation/corrosion, sensitization, and chronic endpoints such as carcinogenicity — including whether ingredients appear on IARC or NTP listings. This is the evidence base behind the health hazards claimed in Section 2.

Section 12 — Ecological information

Aquatic and terrestrial ecotoxicity, persistence and degradability, bioaccumulative potential, and mobility. In the US, OSHA does not enforce the content of Sections 12–15 (they fall to other agencies), but the headings must still appear; EU and Canadian sheets treat these sections as substantive.

Section 13 — Disposal considerations

Safe handling of wastes and appropriate disposal methods, including contaminated packaging. Disposal law is local — point the reader to applicable federal, state/provincial, and local requirements rather than promising a specific waste code applies everywhere.

Section 14 — Transport information

UN number, UN proper shipping name, transport hazard class(es), packing group, environmental hazards (e.g. marine pollutant status), and any special precautions. Dangerous-goods classification follows the transport regulations (49 CFR in the US, and the international modal codes), which are related to but not identical with GHS workplace classification.

Section 15 — Regulatory information

Safety, health, and environmental regulations specific to the product: inventory status (e.g. TSCA), right-to-know listings, SARA 313, California Proposition 65, and — for EU sheets — entries such as the REACH SVHC Candidate List. These are lists, and lists get amended on their own schedules; Section 15 is only correct as of a date, and should say which date.

Section 16 — Other information

Preparation and revision dates, revision notes, abbreviations, key references, and any disclaimers. A clear revision history here makes the sheet's maintenance auditable.

Common mistakes

• Copying a supplier's classification at a different concentration. A supplier's SDS for 35% hydrogen peroxide does not describe your 5% dilution — many substances classify very differently by concentration band, sometimes under specific concentration limits set by regulators. Classify the mixture you actually sell.
• Ignoring jurisdiction-specific Section 1 identity. Shipping a US sheet into Canada or the EU without the locally required supplier and emergency contact details is one of the most common inspection findings.
• Stale Section 15 (and Section 8) lists. Regulatory lists — SVHC, Prop 65, SARA 313, exposure limits — are updated independently of your product. A sheet that was correct at issue drifts out of date while nothing about the product changes. See when to update an SDS.
• Internal contradictions. A flash point in Section 9 that doesn't match the flammability category in Section 2; incompatibilities in Section 10 missing from Section 7; ingredients in Section 3 whose hazards never surface in Section 2. Reviewers and regulators read across sections.
• Blank fields instead of honest statements. "No data available" and "Not applicable" are meaningful entries; silence is not.

Where software-assisted authoring helps

Most SDS errors are not exotic — they are consistency and freshness failures: a classification that doesn't follow from the composition, a regional identity block that didn't get swapped, a list screened three years ago. These are exactly the failures software is good at preventing. A system that computes the GHS classification deterministically from the formulation, screens ingredients against current regulatory datasets, applies the right jurisdictional template for Section 1 and Section 15, and keeps every section derived from one source of truth removes the transcription layer where most mistakes live. Imperium SDS works this way — the classification engine is deterministic and the 16-section render is fixed — with AI used only to review drafts, never to invent hazard data. Whatever tool you use, the final step is the same everywhere: a qualified person reviews the sheet before it ships.

This guide is general educational information, not legal or regulatory advice. Requirements vary by jurisdiction and change over time — always have safety data sheets reviewed by a qualified person before use. See our Terms of Service.

Author SDSs the reliable way. Imperium SDS computes GHS mixture classification deterministically from official regulatory data, renders the full 16-section document for US, Canadian, EU, and Mexican requirements in eight languages, and keeps AI strictly in the reviewer's seat. See plans · More guides