Hazardous mixture notification is one of those obligations that arrives as a surprise. A candle maker, a cleaning brand or a nail products supplier discovers at the point of a customs hold or a retailer audit that their product needed a UFI on the label and a dossier filed with poison centres — and that the compliance chain starts much further back than they thought, with classification and a safety data sheet.
The confusion is understandable, because four separate deliverables sit in one workflow: classification under CLP, the safety data sheet, the UFI code, and the poison centre notification. They depend on each other in a strict order, and doing them out of sequence means redoing them. This guide sets out the full workflow from raw formula to notified product, and where each step tends to go wrong.
Key takeaways
- The workflow runs in one direction: classification → SDS → UFI → PCN → label. Skipping to the end means starting again.
- Notification is required under Annex VIII of CLP for mixtures classified as hazardous for health or physical effects.
- Mixtures classified only for environmental hazards are currently outside the PCN obligation.
- The duty falls on importers and downstream users placing the mixture on the EU market — a non-EU manufacturer cannot discharge it from abroad.
- The UFI is generated free from your VAT number plus a formulation number and must appear on the label.
- All Annex VIII deadlines have passed — consumer and professional use from 1 January 2021, industrial use from 1 January 2024. There is no grace period for new products.
- Reformulating beyond permitted variation means a new UFI, an updated notification and relabelling.
Step 1: Classification — everything depends on this
Nothing downstream can be done until you know how your mixture is classified under Regulation (EC) No 1272/2008. Classification determines whether an SDS is required, whether a PCN is required, what pictograms go on the label, and what the poison centre needs to know.
Classification is based on the hazards of the components and their concentrations, applying the rules and cut-off values in CLP. For most formulated consumer products this is a calculation using classification data for each raw material — taken from supplier safety data sheets and, where available, the harmonised classifications in Annex VI of CLP.
Typical outcomes that trigger everything downstream:
| Hazard class | Common trigger in formulated products | PCN required? |
|---|---|---|
| Skin sensitisation (H317) | Fragrance components in candles, diffusers, detergents | Yes |
| Serious eye damage/irritation (H318/H319) | Surfactants in cleaning concentrates | Yes |
| Aspiration hazard (H304) | Hydrocarbon solvents in diffuser bases, oils | Yes |
| Flammable liquid (H225/H226) | Alcohol-based sprays, room fragrances | Yes |
| Skin corrosion (H314) | Alkaline cleaners, descalers | Yes |
| Hazardous to aquatic environment (H410) only | Some biocidal or preservative-heavy products | No — environmental only |
| Not classified | Many simple formulations | No |
Our explainer on the CLP Regulation covers the classification framework in detail.
Most finished cosmetics are outside this workflow — Regulation (EC) No 1223/2009 governs them and they are notified through CPNP instead. But cosmetic-adjacent products are frequently caught: room and reed diffusers, scented candles, professional salon chemicals, some nail products, and cleaning ranges sold alongside a beauty line. If you make both, do not assume one process covers the other. See PCN vs CPNP.
Step 2: The safety data sheet
Once classified, an SDS is required under Article 31 of REACH where the mixture is classified as hazardous, and must follow the 16-section structure set out in Annex II as amended by Regulation (EU) 2020/878.
Two points matter for the workflow.
First, the SDS is not consumer-facing. It is a business-to-business document for professional users and downstream customers. A consumer product sold at retail still needs a CLP label, but the SDS goes to your distributors, retailers’ compliance teams and — in practice — anyone auditing you.
Second, the SDS is where your classification decisions become written and auditable. If the classification is wrong, the SDS is wrong, the label is wrong and the PCN is wrong. This is why the order matters and why patching an SDS after the fact rarely works. Our guide to what an SDS is and when it is required covers the content.
Since Regulation (EU) 2020/878 applied, the UFI must be included in Section 1.1 of the SDS where one has been assigned — which is the point at which the SDS and the PCN workflow formally connect.
Step 3: Generate the UFI
The Unique Formula Identifier is a 16-character alphanumeric code linking a specific product to the exact composition in a PCN dossier. When a clinician calls a poison centre about an exposure, the UFI on the packaging lets the centre retrieve the precise formulation immediately.
It is generated free using ECHA’s UFI generator from two inputs: your company VAT number and a formulation number you choose yourself. That means UFIs are deterministic — the same inputs always give the same code — so your formulation numbering scheme is worth designing rather than improvising.
Practical points:
- If you have no EU VAT number, ECHA’s system provides an alternative company key route.
- One UFI corresponds to one composition. Multiple trade names sharing an identical formulation can share a UFI.
- Keep a register mapping formulation numbers to UFIs, product names and notification dates. Reconstructing this later is painful.
Our guide to what a UFI code is and how to generate one covers the mechanics.
Step 4: Submit the PCN
The notification goes through the ECHA Submission Portal in the harmonised PCN format, either prepared in IUCLID or built directly in the portal’s online tool.
An Annex VIII dossier is considerably more detailed than a product registration. It requires:
- The full composition of the mixture, identifying components and concentrations — exact values or, within strict permitted limits, concentration ranges.
- The UFI.
- Trade name(s) and the product identifier.
- Classification and labelling information.
- Toxicological information on the mixture.
- The EuPCS product category (European Product Categorisation System).
- Physical state, colour, packaging type and size, pH where relevant.
- The intended use type — consumer, professional or industrial.
Submissions are made per Member State where the product is placed on the market, in the language(s) each requires — but ECHA’s system lets you target multiple countries from a single dossier, which makes multi-market filing far more efficient than filing individually.
The composition requirement is genuinely full disclosure. Many brands are uncomfortable submitting exact percentages, particularly for fragrance formulations, and try to file with vague ranges. The permitted ranges under Annex VIII are narrow and depend on the hazard, and a fragrance house’s refusal to disclose is not an exemption. The usual solution is for the fragrance supplier to make a separate submission for the fragrance mixture and provide you with a reference — arrange this early, because it takes time.
Step 5: Get it onto the label
The final step closes the loop. The CLP label must carry the standard elements — product identifier, supplier details, nominal quantity, hazard pictograms, signal word, hazard and precautionary statements — plus the UFI.
The UFI is preceded by “UFI:” and must be printed on or affixed to the label, clearly visible and legible. For very small packaging where the label cannot accommodate it, Annex VIII allows the UFI to appear on the inner packaging alongside the other label elements in specific circumstances. Our guide to CLP label requirements covers pictograms, signal words and statements in detail.
The notification must be in place before the product is placed on the market. All Annex VIII compliance dates have passed — 1 January 2021 for consumer and professional use mixtures, 1 January 2024 for industrial use — so a new product launched today has no transition period at all.
Keeping the notification current
The most expensive mistake in this whole area is treating the UFI as permanent.
An update to the notification is required when there is a change to the product identifier, the UFI, the classification and labelling, the toxicological information, or the composition beyond the permitted variation limits. Where the composition change goes beyond what the existing dossier covers, you generally need a new UFI, an updated notification and relabelled stock.
| Change | New UFI? | Update PCN? |
|---|---|---|
| Fragrance changed for a new variant | Yes | Yes |
| Concentration of a hazardous component beyond permitted variation | Yes | Yes |
| Classification changes | No | Yes |
| New trade name, same formula | No | Yes |
| New Member State of sale | No | Yes |
| Pack size or packaging type changes | No | Yes |
| Marketing copy only | No | No |
Selling old stock carrying a UFI that no longer corresponds to the formulation inside is a straightforward compliance failure, and it is the finding most likely to come out of a retailer audit.
Who actually carries the duty
The obligation rests with importers and downstream users who place the hazardous mixture on the EU market. Put plainly: whichever legal entity brings the product into EU circulation carries it.
A manufacturer outside the EU cannot file from abroad, so for imported product the duty lands on the EU-based importer. This catches non-EU brands selling direct to EU consumers, who often assume their fulfilment partner has dealt with it. Establish in writing who the importer of record is and who is filing — an assumption on either side means nobody files.
Our guide to importing chemicals into the EU covers how this interacts with wider REACH and CLP duties at the border.
Bringing it all together
The SDS-to-PCN workflow is unforgiving about order but entirely manageable when followed in sequence. Classify the mixture, produce the safety data sheet from that classification, generate a UFI from your VAT number and a controlled formulation number, file the Annex VIII dossier through the ECHA portal for every market you sell in, and put the UFI on the label alongside the CLP elements.
Where companies get into trouble is entering the process at step four — realising a PCN is needed, filing something quickly, and discovering the classification underneath it was never done properly. Everything then has to be redone, usually with product already in the channel. Starting at classification costs less and takes less time, even though it feels like the slower route.
Lexora handles the whole chain, from classifying your mixture and preparing the safety data sheet through to UFI generation and filing via the ECHA portal. Explore our Poison Centre Notification service, or take classification, SDS, labelling and notification together with the CLP Compliance Suite.
Frequently asked questions
Which mixtures need a poison centre notification?
Mixtures classified as hazardous on the basis of their health or physical effects. That includes skin sensitisers, eye irritants, flammable liquids, corrosives and aspiration hazards. Mixtures classified only for environmental hazards are currently outside the PCN obligation, and unclassified mixtures do not need one.
Do I need an SDS before I can file a PCN?
Not as a formal legal precondition, but in practice yes. Both derive from the same classification, and the PCN dossier requires classification, labelling and toxicological information that the SDS also contains. Doing the SDS first means the classification work is complete and documented before you file, which avoids notifying on the basis of assumptions you later revise.
Where does the UFI have to appear?
On or affixed to the product label, preceded by “UFI:”, clearly visible and legible. It must also appear in the PCN dossier itself and in Section 1.1 of the safety data sheet where one has been assigned. For very small packaging, Annex VIII provides limited alternatives such as placing it on the inner packaging.
My fragrance supplier will not disclose their formula. What do I do?
Ask them to make a separate PCN submission for the fragrance mixture and give you the reference to cite in your own dossier. This is a standard route under Annex VIII and preserves their confidentiality while letting you notify completely. Arrange it early — coordinating with a fragrance house takes weeks, not days.
Do I need to notify in every EU country separately?
Notification is required for each Member State where the mixture is placed on the market, and in the languages those states require, but ECHA’s submission system lets you target multiple countries from one dossier. Adding a new country of sale later requires an update to the notification rather than a new one.
What happens if I reformulate?
If the composition changes beyond the variation permitted by your existing dossier, you generally need a new UFI, an updated notification and relabelled stock. Classification changes, new trade names, new markets and packaging changes require an update but not necessarily a new UFI. Selling product whose UFI no longer matches the formulation inside is a compliance failure.
Does my cosmetic product need a PCN as well as CPNP?
Most finished cosmetics do not — they sit under Regulation (EC) No 1223/2009 and are notified through CPNP. But cosmetic-adjacent products such as reed diffusers, scented candles, professional salon chemicals and some nail products can be classified as hazardous mixtures and need a PCN too. Our comparison of PCN vs CPNP explains which applies when.
