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EXPERTISE · DOWNSTREAM USERS

REACH Basics for Downstream Users

You don’t register a substance, but REACH still shapes what you can do with one. Here is where to start.

A downstream user does not register a substance, but still carries real duties.

If you use a substance or mixture in an industrial or professional capacity — in a formulation, a manufacturing process, or repackaged for resale — without manufacturing or importing it yourself, you are a downstream user. That role carries no registration duty, but it does carry real obligations, and your ability to keep using a substance depends on decisions made by suppliers you may never deal with directly.
Since the UK left the EU, downstream users also need to think about this twice over: once for anything supplied into the GB market under UK REACH, and again for anything supplied into the EU under EU REACH, as the two regimes continue to diverge.
Business-critical substance and use inventories
Use description support under ECHA’s Use Descriptor system
Supply chain communication with suppliers and customers
Ongoing monitoring as suppliers’ registrations change
GETTING YOUR OWN HOUSE IN ORDER

Three things to establish before anything else.

These three steps put you in a position to actually exercise your rights and duties as a downstream user, rather than reacting to whatever a supplier happens to send you.

STEP 1
Identify business-critical substances
Build an inventory of what you buy and how you use it: the substances and mixtures behind what you make, the processes you run, and the services you offer. Where you buy in proprietary mixtures rather than named substances, this often takes real digging — a single mixture can quietly contain several substances that turn out to be business-critical.
STEP 2
Collate information on your own use
Work out how you actually use each substance: as an ingredient, in an on-site process, or repackaged and sold on. If you want that use captured in a supplier’s registration, they need a clear description of it. ECHA’s Use Descriptor system, set out in Chapter R.12 of its Chemical Safety Assessment guidance, gives a structured way to describe a use without disclosing anything commercially sensitive.
STEP 3
Engage with the supply chain
Communication with suppliers and customers is left to industry to manage; there is no regulator-provided tool or deadline for it. Once you know how you use a substance, you need to make that use known to your supplier, and pass the resulting safety information down to your own customers in turn.
FIVE KEY OBLIGATIONS

What downstream users actually have to do.

These five obligations sit at the centre of REACH compliance for downstream users, drawn from Articles 34, 37 and 38 and the wider authorisation and Candidate List provisions.

Check you are inside the scenarios you are given
Confirm your use is genuinely covered by the safety data sheet, and any exposure scenarios, you receive. Where it isn’t, you can ask the supplier to include it, notify ECHA or HSE, or in some cases prepare your own chemical safety report.
Report back on hazards and control measures
Tell your supplier about new hazard information, or if the risk management measures they recommend don’t fit your use, or cause problems once applied in practice.
Pass information down the chain
Communicate the hazard information, safe conditions of use and any risk management measures you receive to your own customers — including passing on supply chain communications and safety data sheets you have been given, updated to reflect your own supply where relevant. If you formulate a mixture, you are not required to prepare your own exposure scenario for it, though you can choose to. See our Safety Data Sheets page for what that document needs to contain.
Notify Candidate List use in articles
If you use a Candidate List substance to produce an article, and that use hasn’t been registered for it, above one tonne a year and 0.1% concentration, that use needs notifying to ECHA or HSE.
Respect authorisation sunset dates
Do not continue using an Authorisation List substance after its sunset date unless an exemption applies, or you, or someone upstream in your supply chain, already holds an authorisation covering your use.
Watch for your own Article 33 or Article 66 duties
Depending on your supply chain, the substance and how you use it, you may carry your own Article 33 duty to communicate an SVHC in articles you supply on, or an Article 66 duty to notify ECHA or HSE where you are relying on an authorisation held further up the chain.
GB & EU: TWO SEPARATE SETS OF OBLIGATIONS

Being compliant in one market says nothing about the other.

If you receive the same substance for use in both Great Britain and the EU, you need to check your position against both regimes separately, since a supplier’s registration, and the Candidate List, Authorisation List and restrictions attached to it, can differ between the two.

As a UK REACH downstream user
Your obligations run against substances your suppliers have registered, or are registering, with HSE for the GB market, under the same core duties retained from the original EU regulation.
As an EU REACH downstream user
Your obligations run against substances registered with ECHA for the EU market. A supplier’s UK REACH registration gives you no standing here, and the Candidate List, Authorisation List and exposure scenarios you need to check against are the EU versions, not the GB ones.
HOW WE HELP

Turning a downstream role into an actively managed position.

Being a downstream user can feel passive — waiting to see what a supplier sends you — but the businesses that manage REACH well treat it as an active position instead.
We help organisations build the substance and use inventories that make communicating with suppliers possible, check whether existing exposure scenarios genuinely cover their operations, and monitor Candidate List, Authorisation List and restriction positions that could affect continuity of supply.
Business-critical substance and use inventories
Use description support under ECHA’s Use Descriptor system
Checking your use against suppliers’ exposure scenarios
Candidate List, Authorisation List and restriction monitoring for your role
Next: EXPERTISE
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