SDS vs TDS: What Goes on a Safety Data Sheet vs a Technical Data Sheet
Imperium SDS guides · 2026-08-23
Chemical products typically travel with two documents that are constantly confused with each other: the safety data sheet (SDS) and the technical data sheet (TDS). They often describe the same product, are often requested in the same email, and are often — wrongly — treated as interchangeable. They serve different masters: the SDS is a regulatory safety document; the TDS is a commercial performance document. Keeping them straight matters both for compliance and for not confusing your customers.
The SDS: regulated, mandatory, fixed format
The SDS exists for hazard communication. Under the GHS-aligned systems — OSHA's HazCom 2012 in the US, WHMIS 2015 in Canada, CLP/REACH in the EU — a supplier of a hazardous chemical must provide an SDS, and that SDS must follow the fixed 16-section format: identification, hazard identification, composition, first-aid, fire-fighting, accidental release, handling and storage, exposure controls/PPE, physical and chemical properties, stability and reactivity, toxicology, ecology, disposal, transport, regulatory information, and other information (see our section-by-section guide).
Key characteristics:
- Mandatory for hazardous products — it is not optional collateral, and downstream workplaces are required to have it available to workers.
- Fixed structure — 16 sections, fixed order, fixed headings. You do not get to reorganize it for readability or branding.
- Hazard-focused — its classification (Section 2) is derived from defined rules (see GHS classification, explained), and its audience includes workers, emergency responders, and inspectors.
- Maintained — it must be kept current as hazard information and regulatory lists change (see when to update an SDS).
The TDS: commercial, voluntary, free format
The TDS (also called a product data sheet or technical bulletin) is a marketing and application document. No regulation requires it or dictates its layout. A typical TDS is one to two pages: what the product is, what it's good for, directions for use, a table of typical properties (appearance, density, pH, viscosity, actives content), packaging options, and contact details. "Typical" is doing real work in that phrase: TDS values describe representative production, not guaranteed specifications — sales specifications live in yet another document (a spec sheet or certificate of analysis) when they're contractual.
What belongs on which
| Content | SDS | TDS |
|---|---|---|
| GHS classification, pictograms, H/P statements | Yes — Section 2 | At most a brief hazard overview pointing to the SDS |
| Hazardous-ingredient composition (CAS, ranges) | Yes — Section 3 | No — composition is not marketing material |
| First-aid, fire-fighting, spill response, PPE | Yes — Sections 4–8 | No |
| Physical properties | Yes — Section 9, safety-relevant list | Yes — typical-values table, application-relevant list |
| Performance claims, use cases, dosage/directions | No (Section 1 lists recommended use only briefly) | Yes — this is the point of the document |
| Regulatory listings, transport classification | Yes — Sections 14–15 | Optional one-liners at most |
| Branding, imagery, persuasive copy | Minimal — light theming at most; structure is fixed | Yes — free format |
Why mixing them up causes problems
Performance claims on an SDS. The SDS is a regulated safety document, and everything on it reads as hazard communication. Padding it with marketing copy or typical-performance values buries the safety content, irritates the EHS professionals who are its actual audience, and creates liability-shaped ambiguity: is that viscosity a safety datum or a sales claim? Section 9 should carry the safety-relevant measured properties, stated plainly — nothing is "typical" on an SDS in the promotional sense.
Hazard data only on a TDS. The reverse failure is worse. A TDS that carries the only mention of a product's hazards does not satisfy anyone's hazard-communication obligations — the SDS is the required vehicle, and a workplace audit will ask for it, not the brochure. A TDS also has no obligation to stay current the way an SDS does, so hazard information parked there quietly rots. The sane pattern: the TDS may carry a short hazard overview for the buyer's convenience, always deferring to "see the SDS," and the SDS remains the single authoritative safety document.
The two documents disagreeing. The most common real-world failure is drift: the TDS says pH 12.5, the SDS says 13; the TDS lists a flash point the SDS doesn't; a reformulation updates one document and not the other. Customers and auditors do read both, and a discrepancy between them undermines confidence in each — if the property tables can't agree, why trust the classification?
Keeping them consistent: one formulation, two documents
Drift happens because the documents are usually maintained by different people in different files with no shared source. The fix is structural, not procedural: generate both documents from the same formulation record. When the SDS's Section 9 properties and the TDS's typical-properties table are drawn from one dataset, and the TDS's hazard overview is a summary of the same computed classification that fills the SDS's Section 2, the documents cannot disagree — a reformulation propagates to both, and the commercial document's numbers are the safety document's numbers. This is how Imperium SDS treats the pair: the SDS is composed deterministically from the formulation, and the TDS is built as its commercial companion from the same facts — AI is allowed to organize the marketing prose, but it is barred from inventing numbers, and composition never leaks onto the TDS.
However you produce them, the division of labor is the rule to remember: the SDS answers "is this safe to handle, and how?" under a fixed regulatory format; the TDS answers "what does this do, and why buy it?" in whatever format sells. Each document does its own job, both tell the same story about the same product, and a qualified person reviews the safety document 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.
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