REACH - Applications for authorisation AFA050-01 Chromium trioxide

Closed 22 Sep 2023

Opened 28 Jul 2023


Public consultation on alternatives

Reference: AFA050-01

Applicant: Surface Engineering Association Chromium Trioxide Authorisation Consortium (6 companies – see names on application documents)

Application type: Initial

Substance name: Chromium Trioxide

EC number: 215-607-8

CAS number: 1333-82-0

Proposed use: Use of chromium trioxide for the hard (functional/engineering) chromium electroplating of engineering components as part of an in-house production facility with the purpose of creating a coating to meet specific performance characteristics.

Broad information on use applied for (conditions of use and function): Industrial use of chromium trioxide in hard chromium electroplating processes for components with specific technical performance requirements. Typical components are hydraulic pistons, cylinders and sealing rings, gravure printing components, rotary tooling, shafts and pump rotors, fire protection, components for the production of textiles and printing, press punches, tooling, dies and moulds. All the companies involved in this application carry out in-house hard chromium electroplating. 

Hard chromium plating which represents the surface treatment of metal components with a water-based chromium trioxide mixture (namely chromic acid) to deposit a metallic chromium coating using an electrolytic plating process. The surface of the finished product is entirely free of hexavalent chrome, with the chromium coating being essentially inert. The metallic chromium electroplating coating is fully recyclable.  

In simple terms, electroplating is achieved by passing an electric current between two electrodes which are immersed in an electrolyte bath comprising of chromic acid. One of the electrodes will be the substrate which is to be plated. During the flow of electricity between the two electrodes, chromium atoms are deposited in a layer on the electrode to be plated. The thickness of the resultant chromium plating layer is dependent upon the length of time that the component is left in the chrome plating tank. Hard chromium electroplating has been commercially available since the late 1920’s, and the process has continued to be improved and developed.  

This application covers the use of chromium trioxide for hard chromium electroplating at 6 separate Companies and carried out on an in-house basis.

List of descriptors:

  • Life cycle stage (LCS): Use at industrial site  
  • Sector of end Use (SU): 0 (Other: manufacture of products for automotive and other applications)  
  • Product Category (PC): 14 (Metal surface treatment products)  
  • Process Category (PROC): 1, 4, 8b, 13, 28  
  • Environmental Release Category (ERC): ERC6B  
  • Article Category related to subsequent service life: N/A  
  • Technical Function (TF): Plating agent 

Annual tonnage used: Between 1 and 2 tonnes

Review period requested: 12 years 

How to submit comments

Provide some basic information on possible alternative(s) in the online survey below but more detailed information should be provided in document(s) prepared using the commenting templates in the related section below. A “public version” should always be completed and will be published after the consultation has closed. If you want to include confidential information in your submission, please additionally complete a “confidential version” and submit both versions as attachments.

The consultation lasts for 8 weeks (unless otherwise specified) and closes at 23:59 London time (BST).


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