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How to deviate from standards

​​​​​​​​​It may not be reasonable, in particular circumstances, to comply with a requirement in a Railway Group Standard (RGS) on either a temporary or a permanent basis. A deviation is therefore required.

Deviation application form.

A deviation is a permission to comply with a specified alternative to a requirement in an RGS. A deviation is not a permission not to comply with a requirement in an RGS.

Applying for a deviation

I​f you wish to have a deviation to comply with a specified alternative until a RGS is changed, then you may also wish to submit a request for help f​orm​​ to change the RGS​.  

​Details of how to submit a change proposal for an RGS can be found here.

Who can apply for a deviation?

An application for a deviation from an​ RGS may be made by:

  • Any party who must currently comply, or may reasonably be expected to have to comply in future, with the RGS, or
  • A third party acting on behalf of, and with the support of, any party who must currently comply, or may reasonably be expected to have to comply in future, with the RGS.

Who are the key stakeholders in the process of applying for a deviation?

The key stakeholders in the process of applying for a deviation are:

  • The applicant, who is applying for a deviation from a requirement in an RGS.
  • The affected parties, who must be consulted by the applicant.
  • The Standards Committee, who decides whether to approve a deviation application​ using the decision taking principles which are set out in the RGS Code (the Code) and the Stan​dards Manual ​(the Manual).

How do you prepare for a deviation application?

If you are considering whether to apply for a deviation, or are preparing an application for a deviation, you are strongly advised to consider the Guidance to applicants and members of Standards Committees on deviation applications.

Consultation with affected parties​

The Code requires the applicant for a deviation to consult with all industry parties who are likely to be materially affected by the proposed deviation, prior to submitting a deviation application to Standards Committee for consideration.

Requirements in RGSs define what must be done to achieve technical compatibility on the GB mainline network, therefore you cannot decide to do something different without consulting all affected parties.

Depending on the nature of your operation, affected parties may include:

  • Other railway undertakings (train operators), either passenger or freight
  • Network Rail or other infrastructure manager(s)
  • Owners of assets (for example, ROSCOs)
  • Maintainers, suppliers or contractors.

The applicant for a deviation should provide Standards Committee(s) with copies of any responses to consultation and a summary of any key issues that were raised during consultation, together with how you have responded or intend to respond to those issues.

Other information that could be  provided with the deviation application is the manner in which you contacted the affected parties and the period of time they were given to respond.  This sort of information may be particularly appropriate where you have had a nil return on your consultation, in order to demonstrate to the Standards Committee that you have given the affected parties a reasonable opportunity to comment.

Submitting an application

All deviation applications from RGSs are to be in accordance with the procedure defined in the ​Code and the supporting provisions defined in the Manual.

When do I submit an application?

You should submit an application for a deviation:

  • When you have decided what the alternative arrangements should be.
  • When you have consulted with other industry parties that might be affected by the alternative arrangements.

What do I submit to Standards Committee(s)?

Applications should be made using the deviation application form. All applications should be submitted in electronic format to

The deviation applicant should provide the results of consultation and any additional supporting information.

​It is your responsibility, as the applicant for a deviation, to provide sufficient information to enable the Standards Committee(s) to take an informed decision regarding your application.

Where the Standards Committee believes that the information provided is not adequate, it is unlikely they will be able to consider the deviation at the first available committee meeting, thus delaying the decision. The more relevant, focussed and concise the supporting information, the more likely it is that the Standards Committee will be able to consider the deviation application in a timely manner.

To help you with completing the form, we have made available a few examples of applications at the bottom of this page.

Deviation applications are generally required a minimum of 15 working days (3 weeks) in advance of the Lead Standards Committee meeting.  You can find relevant dates in the Standards Committee meeting dates and associated cut-off dates document. If you are unsure which committee(s) may have an interest in the subject of your deviation application, please contact Joelle Parkhurst on 020 3142 5570.

It is advised that you submit the deviation application form before the cut-off date to be able to respond to any request from the standards committee if and when it arises prior to their meeting.

You should be prepared to present the case for your application to the relevant Standards Committee(s). A Standards Committee may require further information to be provided before the committee can take a final decision, or an application may be modified (with your agreement) by the committee.

Approval and authorisation

Following Standards Committee approval, RSSB will authorise the deviation by the issue of the appropriate Deviation Certificate. The limits to the application of the alternative provisions will be clearly stated in the certificate. In the case of a time-limited deviation, an expiry date will be shown on the certificate.

Authorised deviations are recorded in the deviations register (MS Excel version) deviations register.

The applicant for a deviation is responsible for notifying those industry parties who could be affected by the deviation (and were therefore previously consulted) about the decision of the Standards Committee.

Validity of deviation

The holder of the certificate is responsible for checking that the original assumptions and conclusions contained in the deviation certificate remain valid whenever any material changes occur.

If the conditions of the deviation certificate change, the deviation will no longer be valid. In these circumstances, the holder of the deviation certificate may consider applying for a new deviation. Please inform the Deviation and Proposals team if you no longer require a deviation so that it can be closed (

Individual deviation certificates can be viewed in the Standards catalogue under the relevant RGS and issue number.

Examples of deviation applications

Time-limited deviation applications:

  • GIRT7016 - Interface between Station Platforms, Track and Trains: Liverpool South Parkway Station, Platform 4 extension, isolated columns on platforms
  • GERT8000-HB12 - Duties of the engineering supervisor (ES): New form of High Output Protection Zone - Trials initially planned for Anglia, Wales and Western routes with scope to involve other routes.

Non-time-limited deviations (valid for the lifetime of the asset).

  • GKRT0045 – Lineside Signals, Iindicators and Loyout of Signals: Flashing Aspect Sequence Controls to permit Flashng Yellow aspects to start when Train Approaching Flashing Single Yellow.
  • GERT8075 – AWS and TPWS Interface Requirements: Class 345 Interruption of Overspeed and SPAD Speech Messages on First Cycle.

RIS deviation applications (RIS applications are to gain guidance only).

  • RIS-3440-TOM – Steam Locomotive Operation - 90 mph testing of new build A1 Steam Locomotive 60163 'Tornado' (TOPS 98863).

Note: RIS certificates are issued for guidance only and would include the Lead Standards Committee and the appropriate Supporting Standards Committees' observation and comments.

New franchise holders

If you become the holder of a new franchise, and so join RSSB as a new train operator member, you may find it useful to check what Deviation Certificates the former train operator held.  

You may want to determine if the issue identified by the previous train operator is relevant to your own continued operation, as the Deviation Certificates will only apply to the party to which they were originally granted.  You will need to submit your own application should you wish to deviate in the same or similar way.

​You can find Deviation Certificates issued to any previous train operator by referring to the Deviations Register or the Standards Catalogue.

Further information

If you have any queries regarding deviations, please contact Joelle Parkhurst on 020 3142 5570.

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