Assessment of regulatory needs (ARN) is a process that regulatory authorities use to determine if a substance poses a risk to human health or the environment, and if regulatory action is needed to manage that risk. 

The assessment considers factors such as the hazard properties of the substance, the ways in which it is used, and the potential for exposure. 

The ECHA Universe of Chemicals is the outcome of a comprehensive mapping of substances conducted by ECHA. This mapping assigns each substance to one of six pools based on its regulatory status and ongoing or planned regulatory actions. The information for this mapping is primarily sourced from ECHA's database, which includes information from the REACH registration process, as well as ongoing, planned, and completed regulatory actions. 

The Community rolling action plan (CoRAP) prioritizes substances suspected of posing a risk to human health or the environment for evaluation by Member State Competent Authorities under the substance evaluation process of the REACH Regulation. CoRAP selects substances for evaluation over a period of three years based on established risk-based criteria that include hazard and exposure information, and total registered volumes. Member States have one year to evaluate the selected substances and prepare a draft decision for requesting further information from registrants to clarify identified concerns. The evaluation aims to clarify whether the manufacture and/or use of these substances could pose a risk to human health or the environment.

The dossier evaluation process checks compliance of registration dossiers and contributes to generating relevant data on chemicals. ECHA and the European Commission have published a REACH Evaluation Joint Action Plan to address the lack of compliance in registration dossiers. By 2023, all registration dossiers submitted by the 2018 deadline for tonnage bands over 100 tonnes/year will be screened, and compliance checks will be performed for all substances where data gaps prevent a conclusion on whether the substance is of concern or low priority for regulatory action. The Action Plan requires authorities to make the process more efficient and industry to review their dossiers and generate further information. The dossier evaluation covers compliance checks and examination of testing proposals.

ECHA's endocrine disruptor (ED) assessment list includes substances undergoing ED assessment and discussed by ECHA's ED Expert Group. The list indicates that an informal hazard assessment for endocrine-disrupting properties is under development or has been completed since February 2013. The list provides details on the assessing Member State, assessment outcome, and the latest update to the entry. Further process details and hazard assessment outcome documents are available. If a substance is considered to have ED properties, confirmation through formal risk management and decision-making processes is necessary before any regulatory action can be taken. Some substances may be considered not to have ED properties.

ECHA's PBT assessment list includes substances that are being assessed for their persistence, bioaccumulation, and toxicity properties. The list provides information on the Member State conducting the assessment, the outcome of the assessment, and the latest update. If a substance is found to have PBT properties, further confirmation is required before regulatory action can be taken. Authorities notify their intention to submit a dossier through the Registry of Intentions, and all biocidal active substances undergo a formal PBT assessment.

The registry of harmonised classification and labelling (CLH) intentions until outcome is a database that lists proposals received by ECHA for a new or revised harmonised classification and labelling of a substance. The proposals are submitted by Member State competent authorities, manufacturers, importers or downstream users. Interested parties can track the progress of a proposal through the CLH process, from notification to adoption of the opinion of the Committee for Risk Assessment (RAC). Advance notice allows stakeholders to prepare for commenting later in the process. Anyone with relevant information on the identity or hazard properties of a substance is encouraged to provide this information to the dossier submitter during the early stages of the process or during the consultation. The status of the proposal is indicated as "Opinion Adopted" once the RAC has adopted its opinion.

The registry of restriction intentions is a database that lists the intentions and proposals for restrictions received by ECHA. Restrictions may be proposed by a Member State or by ECHA at the request of the Commission or on its own initiative for substances in the Authorisation List. Member States must notify ECHA of their intention to prepare a restriction dossier. The registry tracks the progress of proposals from notification to adoption by the Committee for Risk Assessment (RAC) and the Committee for Socio-economic Analysis (SEAC) and the European Commission. The advance notice allows interested parties to plan and prepare for commenting during the process.

The registry of SVHC intentions is intended to inform interested parties about substances that are being considered for identification as Substances of Very High Concern (SVHC) by ECHA. Member States or ECHA, at the request of the European Commission, can propose a substance for identification as an SVHC by preparing a dossier in accordance with Annex XV to REACH. The registry tracks the progress of proposals from notification until the outcome, giving stakeholders time to prepare comments during the consultation period. Interested parties can submit relevant information during the consultation, including the identity and hazard properties of the substance.

The REACH Regulation requires ECHA to recommend priority substances from the "Candidate List" for inclusion in Annex XIV (the "Authorisation List") to the European Commission, after considering comments from interested parties and the Member State Committee. The European Commission ultimately decides which substances are included in Annex XIV. Substances not recommended in one round are re-assessed in subsequent rounds and may be included in future recommendations.