REACH - Applications for authorisation AFA056-01 Chromium trioxide

Closed 3 Jun 2024

Opened 8 Apr 2024


Public consultation on alternatives

Reference: AFA056-01

Applicant: Linde AMT UK Ltd

Application type: Initial

Substance name: Chromium trioxide

    • EC Number: 215-607-8
    • CAS Number: 1333-82-0

Proposed use:

Industrial spraying or brush application of chromium trioxide mixtures for the coating of metallic articles subject to harsh environment, to ensure a high temperature corrosion and oxidation resistance, as well as anti-fouling properties or lubricity at high temperature, for automotive, aviation, power generation machinery, Oil and Gas and marine applications.

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

The Applicant uses chromium trioxide solutions to provide anti-corrosion sacrificial coatings on parts subject to harsh environments to ensure a high temperature corrosion and oxidation resistance, as well as deposit-resistant properties of the surface or lubricity at high temperature, for automotive, aviation, power generation machinery, oil and gas and marine applications.

The Applicant’s coatings are mainly used in the aircraft sector in the gas turbine engines and on certain airframe components, and in the power generation industry to extend the life of turbomachinery and provide enhanced efficiency imparted by the smooth surfaces. Less significantly, they are used in the oil and gas market to protect offshore components such as fasteners from severe corrosion and the automotive market to provide corrosion resistance to engine fasteners, exhaust components and hangers.

The Applicant previously identified alternatives in a 2015 AFA submitted to the EU and is in the process of replacing the use of hexavalent chromium mixtures. The three alternatives developed and tested currently allow for 85% of current chromium coatings to be substituted. The Applicant has multiple customer trials underway for performance and processability validation to qualify several other alternatives which might be suitable for completing the substitution of Cr(VI) in their process.

Due to the advancement of the substitution works, the length of the review period requested is short. To finalise the substitution of chromium trioxide, the Applicant has applied for a two year review period until the end of 2026.

List of descriptors:

  • Sector of end use (SU): 17
  • Environmental release category (ERC): 5
  • Process category (PROC):  7, 8b, 13, 21, 22, 26, 28
  • Product category (PC): 14
  • Article category related to subsequent service life (AC): N/A
  • Technical Function: Plating agent

Annual tonnage used: <1 tonne/year

Review period requested: 2 years, end of 2026

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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