The CLH process begins when ECHA receives an intention to prepare a CLH dossier by an MSCA or manufacturer, importer or downstream user. Once the intention is received, a substance identity check is performed, after which ECHA publishes the intentions on the Registry of Intentions on its website.

Besides informing interested parties on the substances that are currently in the process, publishing the intentions for CLH aims to prevent situations in which two or more parties submit a proposal for the same substance at the same time. Moreover, anyone with information relevant to the proposed hazard classification for a substance may bring this to the attention of the party submitting the CLH proposal during the early stages of the process, or provide such information during the consultation.

The CLH dossier prepared by an MSCA or manufacturer, importer or downstream user is submitted to ECHA. The CLH dossier consists of the CLH report and any other supporting information, which is intended to be a ‘stand-alone’ document and must contain sufficient information to allow an independent assessment of physical, health and environmental hazards based on the information presented. The CLH report must not contain any confidential data as it will be subject to consultation.

Further information on preparing and submitting CLH dossiers is available on the page “Submission of CLH intentions and dossiers”.

During this stage, ECHA checks that the submitted CLH dossier is in accordance with the legal requirements of the CLP Regulation. More specifically, that the CLH dossier includes the information needed for RAC to deliver an opinion on the classification proposed in the CLH dossier.

If the dossier is found to be in accordance, ECHA will start the consultation of the proposed CLH as presented in the CLH report on its website. Otherwise, the dossier submitter is asked to bring the dossier in accordance and to resubmit it.

The consultation lasts for 60 days in which interested parties are invited to comment on those hazard classes for which data has been provided in the CLH dossier.

During the consultation, any comments received are published on ECHA’s website.

Once the consultation closes, all the comments and attachments received are compiled and forwarded to the dossier submitter, inviting them to provide their response to the comments (RCOM). The compiled comments and non-confidential attachments are also published on the website at this stage.

The CLH dossier, the comments and attachments received, and the response of the dossier submitter following the consultation, are then forwarded to ECHA's Committee for Risk Assessment (RAC).

RAC examines the available evidence for all hazard classes, which were open to consultation. After a thorough assessment of the relevant data and information, RAC forms its opinion on the proposed CLH. There may be cases where RAC comes to a different classification for a particular hazard class from what was initially proposed by the dossier submitter.

RAC is comprised of experts nominated by the Member States, but acting in their own capacity. A RAC member is appointed as a rapporteur for the dossier, and in most cases, another member is appointed as a co-rapporteur. During the opinion development phase, they will draft the opinion and respond to the comments sent during the consultation and replied to by the dossier submitter.

After the consultation, the parties concerned are encouraged to coordinate any involvement in the RAC opinion-making process with the regular and sector-specific accredited stakeholder organisations. The list of accredited stakeholders, the working procedure for their participation in the RAC meeting and the relevant agendas are available on the Committee for Risk Assessment page. The RAC agendas indicate the substances that are expected to be discussed at designated RAC meetings.

The opinion on the CLH proposal has to be adopted by RAC within 18 months of receipt of a CLH dossier that fulfils the CLP requirements.

The RAC opinion and its annexes (the background document and the RCOM table) are published on ECHA’s website once the opinion is adopted. The background document is based on the CLH report in which RAC evaluations are inserted. The RCOM contains the compiled comments received during the consultation and the responses by the dossier submitter and RAC.

ECHA sends the RAC opinion along with its annexes to the European Commission for its decision.

The Commission, assisted by the expert group CARACAL (the Competent Authorities for the REACH and CLP Regulations), prepares a delegated act for the classification and labelling of the substances concerned, in accordance with the CLP Regulation and with consultation of stakeholders.

The Commission adopts the delegated act and notifies the Council and the European Parliament who after a period of objection include the substances in Part 3 of Annex VI to the CLP Regulation. Delegated Acts are published in the Official Journal after the expiry of the objection period.

Following the inclusion of the substance in Part 3 of Annex VI to the CLP Regulation, all manufacturers, importers and downstream users of the substance in the EU must classify the substance in accordance with the entry in Annex VI. Hazard classes not included in the Annex VI entry must be self-classified and labelled accordingly. The Classification and Labelling Inventory includes the list of harmonised classifications but also contains classification and labelling information on notified and registered substances received from manufacturers and importers.

If the harmonised classification of the substance needs to be re-assessed, a Member State might submit a new CLH proposal with data supporting the proposal for revision of an existing Annex VI entry. The CLH dossier would then go through all the steps listed above.

If industry has data suggesting that a change in a harmonised classification is warranted, they must submit a CLH report to an MSCA.

In some cases, ECHA Executive Director may request RAC to draw up an opinion on any other aspects concerning the safety of substances on their own, in mixtures or in articles. This way, RAC may be given a mandate to address one or more specific issues related to classification and labelling. A consultation may be held to assist RAC in adopting its opinion. However, such a request from the Executive Director cannot on its own lead to a harmonised classification.

Only the topics defined in the mandate are addressed and comments may only be requested on the defined hazard class or question for which the mandate has been given. RAC will limit its assessment to that specific hazard class or question.