RoHS vs REACH: Two Compliance Words Everyone Mixes Up

RoHS and REACH are two European regulations that appear side by side on almost every component declaration, and they are not two versions of the same thing. One restricts specific substances in electrical equipment; the other regulates chemicals generally, including those used in any product. Understanding the difference answers the practical question of which one your order needs.

Two regulations, two goals

RoHS is about what may be present in electrical and electronic equipment, and it works by banning a short list of substances above defined limits. REACH is about chemicals as such, across every industry, and it works by requiring registration, authorisation and communication rather than by banning most things outright.

The analogy that fits is two rules about food. One says a particular ingredient may not be in a particular product above a threshold; the other says that anything in the product must be declared and that some ingredients need approval. Both affect what is on the shelf, and neither substitutes for the other.

RoHS in one paragraph

RoHS restricts lead, mercury, cadmium, hexavalent chromium, two classes of brominated flame retardants and four phthalates in electrical and electronic equipment, with exemptions where no substitute is technically available. Compliance is demonstrated by a declaration against the restriction, covering a defined scope of products or part numbers. Its focus is a closed list and a product category.

REACH in one paragraph

REACH covers chemicals manufactured, imported or used in the European Union, and its obligations apply across all product types rather than to electronics specifically. The part that matters most to component buyers is the candidate list of substances of very high concern: if an article contains one of those above a defined concentration, the supplier has a duty to communicate that information to the customer, and the customer may in turn have duties of their own. There is also provision for authorisation for certain uses.

The key difference in practice is the direction of the obligation. RoHS asks whether a banned substance is present. REACH asks whether a listed substance is present and, if so, whether it has been communicated. One is a prohibition; the other is largely a disclosure duty.

Why the confusion happens

Four reasons. They appear together on the same declaration, which makes them look like two parts of one requirement. Both are European. Both are usually satisfied by the same document, so buyers stop distinguishing them. And both are often referred to in the same breath as “compliance”, which is a word that carries no information on its own.

The practical harm is small for a buyer who just needs the documents, and larger for someone designing a compliance programme, because the two impose different obligations at different points in the supply chain. A component supplier’s REACH duty may be to communicate, while its customer’s duty may be to pass that communication further down or to notify a regulator.

The SVHC list and threshold

The candidate list of substances of very high concern is maintained and updated over time, which is why a declaration that was accurate last year may need reissuing. The relevant concentration threshold for the disclosure duty is a small percentage by weight in an article, and the technical difficulty lies in establishing that figure with confidence when a component is assembled from several materials.

Two practical consequences follow. A REACH statement should carry a date, because the list it was assessed against changes. And the answer to “does my product contain a listed substance” is a supply-chain question rather than a materials-science one, because the information has to come from each supplier in turn.

What a supplier must provide

For RoHS, a declaration of compliance covering the part numbers being supplied, dated and issued by the manufacturer. For REACH, a statement about the presence of listed substances in the article, ideally with the concentration bands used, also dated and issued by the manufacturer or an authorised representative.

Both documents should name the scope. A statement that covers a product family is a starting point; for a regulated purchase you want the specific part number, because that is what will be shipped and what an auditor will ask about. Where a supplier can only provide a family-level statement, that limitation is worth recording with the order.

Which one applies to your order

Both, if the product is placed on the European market. They are not alternatives, and a supplier who offers one instead of the other has answered a different question from the one you asked.

The practical checklist for a purchase is therefore short: a RoHS declaration covering the part number, a REACH statement covering the same part number, both dated recently enough to reflect current composition and current chemical lists, and both from the manufacturer rather than from a reseller. Anything less is a document gap that will surface at the wrong moment.

How the two are asked for in practice

Most component makers answer both questions on one page, which is convenient and slightly misleading. The RoHS half is a statement of compliance against a list; the REACH half is a statement about the presence of substances on a list that is revised. Those two halves age differently, so a single document can be current for one purpose and out of date for the other.

The habit that avoids the problem is to treat the page as two documents and check each on its own terms. For the compliance half, check the scope and the restriction it names. For the chemical half, check the date and which version of the list was used. If one half is stale, ask for that half to be reissued rather than accepting a fresh-looking template with an old assessment behind it.

There is also a wording trap. A statement that a product “contains no SVHC above 0.1 per cent” is not the same as a statement that it contains none at all, and it is not the same as a statement that no SVHC is present. The threshold, the units and the concentration basis all change what has been claimed, so the safe approach is to ask what was assessed and how, rather than to accept a sentence that sounds stronger than the test behind it.

None of this requires a legal background. It requires reading two lists of questions and checking whether the answer addresses the one you asked. A supplier with a working compliance process will recognise the questions immediately, because they are the same ones its own customers ask.

External references are the right place to take this further, because both regimes change. The European Commission publishes the RoHS Directive and its exemptions, and the European Chemicals Agency publishes and explains REACH and the candidate list. Component test methods come from JEDEC, materials and assembly expectations from IPC, and quality management requirements from ISO. Regulatory and quality background is published by NIST.

Side-by-side table

FAQ

What to do next

Before your next regulated purchase, ask for both documents and check that each names the part number you are buying and carries a recent date. That request takes one email and answers the question a compliance questionnaire will eventually ask. The adjacent manufacturing consequence of the substance restrictions is covered in our article on why lead-free solder changed manufacturing.

This article is published by Good-Ark, a manufacturer of discrete semiconductor devices. It describes two regulatory frameworks at a summary level; thresholds, scope, exemptions and the current substance lists belong to the official texts, and no product-specific compliance claim is made here.