| Document | Question it answers | Issued | Who needs it |
|---|---|---|---|
| CoA Certificate of Analysis | Did this batch meet the specification, and what were the measured values? | Per batch | Quality assurance, incoming goods, your customer's audit |
| TDS Technical Data Sheet | What is this material, what is it typically used for, and how should it be handled and stored? | Per product | Formulation, R&D, purchasing |
| SDS Safety Data Sheet | What are the hazards, and how do I protect people, transport it and dispose of it legally? | Per product, revised when the classification changes | EHS, logistics, warehouse, regulatory affairs |
CoA: the only document that is batch-specific
A Certificate of Analysis is a statement of measured results for one specific lot. It should carry the product name, CAS number, batch or lot number, manufacturing date, retest or expiry date, the specification limit for each parameter, the measured result, and a conclusion against specification, signed by the person releasing the batch.
For our products a CoA typically reports appearance, assay by GC or HPLC, water content (Karl Fischer), colour, and any product-specific parameters — acid value for esters, individual impurity limits where the specification calls for them. If a parameter is not on the CoA, it was not measured for that batch; that is the point of the document, and it is why a generic “typical properties” table cannot substitute for it.
Practical test: a CoA without a batch number, a manufacturing date and a specification column is a marketing sheet, not an analysis. Ask for a real one before you approve a supplier.
TDS: the formulation-facing document
The Technical Data Sheet describes the material rather than a specific batch. It covers identity (INCI, CAS, EC, formula, molecular weight), typical physical properties, solubility and compatibility, suggested applications and use levels, packaging, storage and shelf life, and the regulatory status the supplier is prepared to state.
This is the document to read when you are deciding whether an ingredient fits a formula. It is also the document most often written loosely: “typical” values are not guaranteed values, and a TDS that quietly omits the assay range is telling you something. Our TDS states the specification range we actually release against.
SDS: 16 sections, and it belongs to the supplier
A Safety Data Sheet follows the GHS 16-section format and covers identification, hazard identification, composition, first-aid, fire-fighting, accidental release, handling and storage, exposure controls, physical and chemical properties, stability and reactivity, toxicological information, ecological information, disposal, transport information, regulatory information and revision history.
Two points that cause real problems in audits. First, an SDS is issued by the company placing the substance on the market, so an SDS from another supplier is not valid for our material — the composition, impurities and classification can differ. Second, section 14 is the authoritative transport classification; a webpage is not, and neither is a freight forwarder's assumption.
We issue English GHS-format SDS documents; a Chinese-language SDS is available for products shipped domestically. If your EHS department needs an SDS in another EU language, tell us at the quotation stage and we will confirm what is possible before the order is placed rather than after.
Getting documents quickly
- TDS: available immediately from the document form on each product page, no qualification required.
- SDS: sent by email on request, normally within one working day.
- CoA: issued with the shipment for the actual batch. If you need to review a CoA from a previous lot before ordering, ask — we would rather you saw the real numbers first.
Regulatory documentation: what we can and cannot provide
This is the part of supplier qualification that most often goes wrong, so we prefer to state it plainly rather than let it surface during an audit.
What we provide
- CoA, TDS and English SDS for every product in the range.
- Specification sheet with the parameters and limits we release against.
- GHS classification, HS code and a statement of country of origin.
- A written statement of the regulatory position per product, including whether the substance is listed in the main inventories (EU, US TSCA, and others on request).
- Confirmation of ISO 9001:2015 certification status in writing.
What we do not provide, and why
- REACH registration numbers in our own name. Qingdao Marram Chemical is established in China, not in the EU, and is therefore not eligible to register substances under REACH. Registrations in the EU are held by EU manufacturers, importers or Only Representatives.
- Organic or natural certification for synthetic products. We do not hold COSMOS or equivalent approvals and will not imply them.
- Certificate scans and plant photography. Our manufacturing partner's certification can be confirmed in writing, and where a signed document is required for your audit it is handled through the sales contact under NDA rather than published on a website.
- Monograph conformity claims (for example USP or EP) unless the batch has actually been tested against that monograph. Ask, and we will tell you what the batch was released against.
REACH and UK REACH in one paragraph each
EU REACH. If your company imports a substance into the EU above one tonne per year, the registration obligation sits with your company as importer, unless your non-EU supplier has appointed an Only Representative who registers on its behalf. For dicaprylyl ether (CAS 629-82-3) the substance is already registered in the EU by other parties, so coverage can normally be arranged through your importer registration or an Only Representative without commissioning new vertebrate testing. For products where the substance is not yet registered at your tonnage band, the timeline and cost sit with the registrant, which is why this is worth resolving before a first order rather than after.
UK REACH. Great Britain operates a separate regime administered by HSE, with its own registration and data-submission deadlines that fall later than the original EU schedule. A UK importer faces the same structural question: who holds the registration, and does the supply chain have access to the data. Do not assume an EU registration covers a GB import — it does not.
A checklist to send to any Chinese supplier
Are you the producer or a trader?
Ask for the production site and the name of the entity that releases the batch. A trader cannot issue a meaningful CoA.
Send the CoA for the last three lots
Three lots reveal variability that a single document hides — colour drift, assay spread, water content.
What is your release specification, not your typical value?
A supplier who cannot separate the two does not have a quality system, whatever the certificate on the wall says.
Which SDS do you issue, and in which language?
Confirm the issuing entity on the SDS matches the company on the invoice.
What is the regulatory status of this substance in my market?
Ask for it in writing, per product, and compare it with what your own regulatory team concludes.