A technical data sheet, or TDS, describes a chemical product: what it is, its typical properties, what it is used for, how to handle it and how it is packed. It tells you whether the product suits your application.
A TDS is not a safety document and not a test result for a batch. Safety information belongs in the safety data sheet. Results for a specific lot belong in the certificate of analysis.
What a good TDS includes
- The product name, chemical name or description, and CAS number where it is a single substance.
- The grade and the intended applications.
- A table of properties: appearance, assay or active content, moisture, pH, density, viscosity, melting point or other key values.
- For each property, the unit and the test method used, such as an ISO or ASTM standard or an in-house method.
- Whether each value is a typical value or a specification limit.
- Directions for use, dosage or compatibility, where relevant.
- Storage conditions and shelf life.
- Pack sizes and pack types available.
- A revision date and the issuing company.
Typical values versus specification
This is the most important point when you read a TDS. Many TDS tables show typical values. A typical value describes an average batch. It is not a promise that every batch will reach it.
A specification is a limit, such as assay not less than 98.0%. Only specification limits are worth putting in your contract. If the TDS mixes both without saying which is which, ask the supplier for a separate product specification sheet.
Common gaps in Indian TDS documents
Smaller suppliers often issue thin TDS documents. Watch for these gaps:
- No test methods, so you cannot reproduce the results in your own lab.
- Values copied from a competitor's or a reference product's sheet.
- No revision date, so you cannot tell whether the product has changed.
- Ranges so wide that almost any material would pass.
A thin TDS does not mean a poor product. It does mean you need to write your own specification and have the first lots tested. Our guide on reading a lab certificate helps with the next step.
How to use a TDS when sourcing
Collect the TDS from every candidate supplier and line them up in one table. Compare the same properties, measured by the same methods. Note where one supplier gives a value and another leaves it blank. Then ask each supplier to turn its typical values into specification limits it will guarantee. The gap between the two shows you how much variation to expect between batches. Keep each TDS on file with its revision date. If a supplier issues a new version later, compare it with the old one and ask what changed in the product or process.
Next step
We collect and check the TDS, SDS and COA for each product and turn them into a specification you can contract on. Book a free sourcing review.