REACH - Applications for authorisation AFA030-01 Sodium dichromate

Closed 19 May 2023

Opened 24 Mar 2023


Public consultation on alternatives

Reference: AFA030-01

ApplicantBrenntag UK Ltd

Application type: Review

Substance name: Sodium dichromate

EC Number: 234-190-3

CAS Number: 10588-01-9

Proposed use: Passivation of stainless steel using sodium dichromate in the Aerospace and Defence industry and its supply chains.

Broad information on use applied for (conditions of use and function): 

This use covers passivation of stainless-steel using sodium dichromate (SD) in the aerospace and defence industry and its supply chains where any of the following key functions are required: corrosion resistance, embrittlement/heat treatment, (should not induce hydrogen embrittlement), and adhesion to subsequent layer.  Passivation of stainless steel involves the removal of embedded iron/steel particles from the substrate, and formation of protective chromium oxide on the surface. It is these processes that provide the key functions of passivation.   An alternative must be compliant with any heat treatment process required to purge hydrogen. In addition it must not impact upon performance requirements such as fatigue strength and chemical resistance.  These performance requirements must be considered when selecting test candidate alternatives.

The applicants have identified a shortlist of potentially suitable alternatives. Due to the complexity of design challenges, performance requirements, safety requirements and regulatory controls that must be tested for each listed alternative, and the need for industrial implementation in the whole supply chain, the applicant is seeking a review period of 12 years. 

This “applied for use” involves the continued use of SD across approximately 25 sites across Great Britain (GB).

List of descriptors:

  • Sector of end use (SU): Other: Aerospace and defence industry and its supply chains
  • Environmental release category (ERC): 6b
  • Process category (PROC): 0, 5, 8b, 9, 10, 13, 15, 28 
  • Product category (PC): 14 
  • Article Category related to subsequent service life (AC): N/A 
  • Technical Function: Corrosion resistance; Embrittlement/heat-treatment; Adhesion to subsequent layer

Annual tonnage used: 

  • Sodium dichromate – Up to 5 tonnes/annum

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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