scope:

This standard applies when making an alteration to the Authorised Line Speed on a section of line for one or more Category of Train. This includes introduction of an Authorised Line Speed for a different Category of Train on that line that did not exist previously.

The requirements of this standard apply specifically to those responsible for sponsoring the change and those involved in managing the change. The requirements of this standard shall be applied in any of the following circumstances:

• an increase, decrease, introduction or withdrawal of:

- permissible speeds

- standard differential speeds (i.e. freight trains)

- non-standard differential speeds (i.e. HST, MU, EMU, DMU, SP or CS)

- Enhanced Permissible Speeds (EPS)

• an increase or decrease in junction/turn-out speeds

• a change from mph to kph (or vice versa)

• introduction of speeds on newly constructed or regenerated sections of line

• conversion of Temporary Speed Restrictions (TSRs) to Permanent Speed Restrictions (PSRs) of the same value

NOTE This standard should be regarded as best practice when removing long-term TSRs (defined as those that have been in place for 6 months or more) and reverting to the original PSR.

Specific requirements of this standard, detailed in Section 6.3, apply when making an alteration to the location of a speed change but where the speed values remain unchanged.

The means of indicating/recording the Authorised Line Speed covered by this standard are as follows:

• by permanent lineside signage (or temporary lineside signage in the case of TSRs)

• within Table A of the Sectional Appendix

• on the Signalling Plan

Measurements of speed covered by this standard include:

- miles per hour (mph)

- kilometres per hour (kph)

Purpose

The purpose of this standard is to set out the process requirements prior to making alterations to Authorised Line Speeds. The aim is to provide a consistent means of managing such changes so that the risk to passengers, the workforce and public is reduced so far as is reasonably practicable. It also defines the documentation to be produced and retained of the considerations made and decisions taken in the process.