ISO 24675-1:2022

Overview

ISO 24675-1:2022 - "Railway Applications - Running time calculation for timetabling - Part 1: Requirements" defines the parameter requirements and verification approach for calculating the shortest running time between adjacent stopping or passing points on a rail route. The standard focuses on the inputs and checks needed to produce accurate, punctual timetables (daily and annual) rather than prescribing a specific mathematical calculation method. It is intended to help infrastructure managers, railway operators and related organizations improve timetable punctuality, network capacity and operational planning.

Key topics and technical requirements

The standard identifies and requires the preparation of infrastructure, rolling‑stock and operational parameters that significantly influence shortest running time. Major elements include:

• Scope and purpose

  • Shortest running time between two adjacent stopping/passing points as the minimum unit for timetabling.
  • Excludes running time calculations for non‑timetabling purposes.

• Infrastructure parameters

  • Range of calculation (start/end positions in meters)
  • Gradient and changing positions (‰ and m)
  • Allowed maximum infrastructure speed and position changes (km/h, m)
  • Speed limits from infrastructure conditions (km/h, position, length)
  • Positions of tunnels, curves, neutral sections, switches, etc.

• Rolling stock parameters

  • Train mass (kg)
  • Maximum operational speed (km/h)
  • Train length (m)
  • Unit running resistance force (N/kg)
  • Tractive force (N)
  • Braking deceleration (m/s²)

• Operational parameters

  • Stopping or passing definitions for start/end points
  • Maximum speed under specific operational conditions (km/h)

• Verification

  • Clause 6 prescribes verifying the influence of each parameter by observing responses in calculated shortest running time when parameter values change, to confirm appropriate parameter application.

Practical applications and users

ISO 24675-1 is intended for professionals and organizations involved in rail timetabling and operations, including:

• Railway infrastructure managers and planners
• Train operating companies and timetable engineers
• Rolling stock planners and vehicle performance analysts
• Software vendors developing timetable and simulation tools
• Capacity analysts, crew and depot schedulers

Typical applications:

• Establishing punctual and feasible daily and annual timetables
• Calculating baseline shortest running times to set headways and connections
• Supporting rolling stock and crew rostering, station and depot operation planning
• Improving service punctuality and increasing network capacity

Related standards

• Part 1 is the requirements element of a multi‑part series on running time calculation for timetabling. Additional parts will complete the comprehensive guideline for railway timetabling.
• Prepared by ISO/TC 269 (Railway applications), SC 3 (Operations & Services).

Keywords: ISO 24675-1, running time calculation, shortest running time, timetabling, railway infrastructure, rolling stock parameters, timetable verification, punctuality.