SDS vs Technical Data Sheet: What Each One Tells You

Two PDFs land in your inbox from the same raw material supplier, both a few pages long, both full of technical-looking detail, and it's genuinely easy to mix them up if you're new to sourcing. The Safety Data Sheet and the Technical Data Sheet look like siblings but they're answering completely different questions, and only one of them is going to help when you sit down to fill out a Cosmetic Notification Form.

What each document is for

The Safety Data Sheet, or SDS, exists to communicate hazard and handling information. It's built around a standardized 16-section format, covering things like hazard identification, composition, first aid measures, handling and storage, and disposal considerations. Its audience is broad: warehouse staff, shipping companies, emergency responders, anyone who needs to know how to handle the substance safely, not just formulators.

The Technical Data Sheet, or TDS, exists to describe performance. It tells you what the ingredient does, its typical physical properties, recommended use levels, solubility, pH range, appearance, and often some guidance on how to incorporate it into a formula. Its audience is narrower: the formulator actually deciding whether and how to use this raw material.

A side by side comparison

Question you're asking	Which document answers it
What's the CAS number and general composition?	SDS, Section 3
What hazard pictogram or handling precautions apply?	SDS, Section 2
What's the recommended use level in a formula?	TDS
What's the ingredient's appearance, odor, pH, solubility?	TDS
How do I store or dispose of this safely?	SDS
What's the INCI name I should use on my filing?	Neither reliably by itself, cross-check both against your formula records

Why formulators reach for the wrong one

It's a common instinct to grab whichever document is handy when you need a quick answer, and both documents often sit in the same supplier folder, sometimes even bundled into a single download. But asking a TDS for hazard classification information gets you nothing useful, TDS documents generally don't include GHS pictograms or hazard statements. And asking an SDS for a recommended use level is just as much of a dead end, that's not the SDS's job either. Section 3 of an SDS might mention a concentration range if the material is itself a mixture, but that's about composition disclosure, not formulation guidance.

Where INCI and CAS actually come from

This is the part that catches people out. Neither document is guaranteed to hand you a clean INCI name on a platter. The SDS's Section 3 often lists composition using CAS numbers and sometimes chemical names that aren't identical to INCI nomenclature. The TDS often uses the supplier's trade name prominently, with the INCI name mentioned once, or sometimes not at all if the product is a proprietary blend. Getting from "what the supplier calls it" to "the INCI name and CAS number I put on my Cosmetic Notification Form" frequently means reading both documents together and sometimes following up directly with the supplier's technical contact.

For a blended raw material, a premix or a proprietary complex, this gets more involved still. The TDS might describe the blend's overall function and use level, while the actual INCI breakdown of individual components, and their percentages within the blend, might require a separate ingredient statement or certificate of composition entirely.

A practical filing habit

Keep both documents on file for every raw material you use, and treat them as complementary rather than interchangeable. Pull hazard and handling context from the SDS, pull use-level and performance guidance from the TDS, and confirm INCI names and CAS numbers by cross-referencing both against your own formula documentation, following up with the supplier directly when either document is ambiguous or the ingredient is a proprietary blend.

Cosmetic Comply's ingredient matching draws on whatever supplier documentation you have, SDS, TDS, or certificates of composition, to confirm INCI names and CAS numbers and expand blends into their real components, so the gap between "what the supplier calls it" and "what needs to go on the notification" gets closed properly rather than guessed at. If you've only ever skimmed one of these two documents per ingredient, it's worth going back and reading the other one too. They're telling you different things, and your filing needs both.