REACH - Applications for authorisation AFA047-01 – Chromium Trioxide

Closed 29 Jan 2024

Opened 4 Dec 2023


Public consultation on alternatives

 Reference: AFA047-01

Applicant: Tyco Electronics UK Ltd

Application type: Review report

Substance name:

Chromium Trioxide (includes “Acids generated from chromium trioxide and their oligomers", when used in aqueous solutions).

EC Number: 215-607-8

CAS Number: 1333-82-0

Proposed use: Industrial use of chromium trioxide in conversion coating and passivation of circular and rectangular connectors in order to meet the requirements of international standards and special requirements of industries subject to harsh environments.

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

Under this use, Tyco Electronics UK Ltd uses chromium trioxide in the conversion of connectors and backshells intended to function in harsh conditions both atmospheric and mechanical (humidity, temperature, vibrations, corrosive atmosphere). The surface treatment of the connector shells, either plated, or just as base metal, is performed in bath treatment lines. The parts are manually dipped in successive baths including a treatment bath containing hexavalent chromium.

This process yields high performance connectors intended for specific applications (military, aeronautics, space, etc). The main performance requirements which have to be met by these connectors include:

  •  Corrosion resistance
  •  Conductivity
  •  Colour
  •  Thickness
  •  Temperature resistance

This "applied for use" involves the continued use of chromium trioxide at 1 site in Great Britain (GB).

List of descriptors: 

  • Sector of end use (SU): 17
  • Environmental release category (ERC): 5
  • Process category (PROC): PROC 7, PROC 8a, PROC 13, PROC 15, PROC 21, PROC 26, PROC 28
  • Product category (PC): 14: Metal surface treatment products
  • Article category related to subsequent service life (AC): 7
  • Technical Function: Plating agents and metal surface treating agents

Annual tonnage used: 0.3-1.2 tonnes/year

Review period requested: 7 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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