Research ready to use
CHAMOIS tool ready to make safety management more efficient | Does your PDP need an update?
Advances in remote axle bearing monitoring | Existing locomotives can haul heavier loads
A standard way of classifying hazards, to be used throughout the GB rail industry.
The Common HAzards for the Management of Industry Safety tool (CHAMOIS) consists of a baseline hazard list and a baseline rail system ontology list, each structured in three hierarchical levels, with successive levels including more detail. Together, the hazard list and ontology can be used as a prompt to identify and categorise all foreseeable and meaningful hazard scenarios on the railway network.
The benefit to industry of the CHAMOIS lists is that they provide a common language and a benchmark baseline to improve consistency in hazard identification and risk assessment.
The work supports the implementation of the industry strategy Leading Health and Safety on Britain’s Railways, and will enable robust risk-based decision making as outlined in the industry policy document Taking Safe Decisions.
The Generic Hazard Lists are available now. They can act as a baseline for project teams to use in risk assessment, or provide an independent check of an organisation’s own hazard identification activities.
We will continue to review and quality check the CHAMOIS tool as the hazards lists are put into use across the industry. We welcome your feedback and suggestions for improvements or enhancements to these lists.
To read about the research underpinning the hazard lists, go to the RSSB Research Catalogue and search for T1194.
Contact Ben Gilmartin, Principal Risk and Safety Intelligence Analyst, with any questions or feedback, or to request a presentation of the tools: Ben.Gilmartin@rssb.co.uk
Dynamic Response Analysis (DRA) could detect axle bearing failure at an early stage, cutting costs and disruption.
The freight industry invests heavily in maintaining and inspecting axle bearings, because any failure presents a significant derailment risk. This research shows that applying new monitoring technologies would reduce the risk of derailment and save on maintenance and inspection.
The hot axle box detectors (HABD) currently distributed around the network detect failures when the bearing has already failed, and immediate action is needed. When HABDs are triggered, freight and passenger trains must be stopped so inspection can take place. This causes significant disruption to services, with cost to the industry.
Advances in remote condition monitoring and dynamic frequency analysis (DFA) could provide an alternative monitoring system. The latest Dynamic Response Analysis (DRA) technology has the potential to detect degradation much earlier, while it poses no significant risk to safety. The technology takes intermittent measurements over a long period of time, providing the maintainer with an opportunity to plan maintenance in advance, significantly reducing any disruption.
There are two distinct DRA systems:
On-vehicle, with multiple sensors installed on each vehicle/wagon.
Track-side, with sensors placed strategically around the network to monitor vehicles as they pass by.
The research found that on-vehicle sensing returns medium benefit to cost ratios, due to number of sensors required, their cost, battery life, and expected replacement. However, 'track-side' monitoring returns a high benefit to cost ratio. It is a mature and available technology and could unlock this capability with about 20 installation locations. Track-side monitoring capability can also be exploited to maintain passenger vehicles.
The two systems can coexist: track-side can be deployed now, with on-vehicle providing additional cover for high-risk or higher-value wagons.
The findings make a strong case for change. We encourage freight operators, wagon owners and Network Rail to start investment in this new axle bearing monitoring technology.
The proactive monitoring and management of potentially faulty axle bearings in service using dynamic frequency analysis gives safety and cost benefits. Understanding the different use cases and types of monitoring systems that are available enables decisions that deliver the best value for money and are the most appropriate to the rolling stock being operated on a route.
To read more about the project: go to the RSSB Research Catalogue and search for T1267.
Watch a presentation about axle bearing monitoring.
To discuss the work, contact Robert Staunton, Research and Innovation Account Manager: Robert.Staunton@rssb.co.uk
A fresh look at the way maximum tonnage is calculated has unlocked extra capacity.
The maximum tonnage (trailing load limit) a freight train can haul depends partly on the power of the locomotive. This research has re-examined the engineering principles behind how the limits are calculated. The findings enable heavier loads to be carried using existing locomotives.
Trailing load limit thresholds are detailed within a Network Rail document known as the Freight Train Loads Book. It has not been recently revised and does not include any locomotive classes introduced this century.
The methodology for calculating trailing load limit has also remained largely unchanged. It was first standardised in the ‘Manual of maximum freight train loads on gradients for various types of locomotives’, and its technical details date back to 1969. The methodology and assumptions underpinning the standard were derived for locomotives present on the network at the time.
RSSB’s research projects are bringing modern thinking and analysis to age-old issues enabling more goods to be hauled by train without needing investment in new infrastructure or rolling stock.
This project has redefined the methodology for calculating trailing load limits to accommodate advances in locomotive capabilities, such as better traction control, as well as extending the range of locomotives considered. The work will allow Network Rail to reissue the Freight Train Loads Book with greater locomotive coverage and accuracy. In the meantime, we are working with freight operators to take advantage of these new values, alongside applying the findings from research into freight coupler strength (T1256).
Keep up to date with this project and its findings – go to the RSSB Research Catalogue and search for T1302.
RSSB will be supporting freight operators to be early adopters of the increased trailing load limits. To find out more, contact Aaron Barrett, Lead Research Analyst: Aaron.Barrett@rssb.co.uk
New guidance on creating driving policies that make full use of modern rolling stock and infrastructure.
All train operators have a Professional Driving Policy (PDP) that provides additional guidance on safe driving through a combination of personal attitudes, behaviours, non-technical skills, and train driving techniques.
The industry does not have a consistent approach to creating and reviewing PDPs. There is a concern that some policies are not exploiting the full technical capabilities of new rolling stock, or not fully utilising the design of the infrastructure. Rather than reducing risk, some PDPS might in fact be increasing whole system safety risk.
Defensive driving techniques are considered a core component of a PDP. The techniques encourage the driver to anticipate and respond appropriately to operating and environmental conditions. Defensive driving is instilled into drivers throughout their training, and regularly monitored and assessed by driver competency assessors.
Driver participant in the research
The introduction of defensive driving in the 1990s, following the Southall and Ladbroke Grove accidents, led to a marked decline in the number of SPADs. However, in recent years the trend in SPAD numbers has reversed. With the culture of defensive driving fully embedded in the industry, it suggests that SPAD risk cannot be reduced further by simply driving slowly and cautiously.
Defensive driving decreases average velocity. In turn this reduces network capacity (system utilisation) and timetable resilience. Within the industry, there are concerns that defensive driving practices are inadvertently increasing operational risks through inefficient use of signalling capacity. Trains clear signalling sections more slowly, so drivers will see more restrictive aspects.
This research project reviewed the professional driving policies for 23 train operating companies, five freight operating companies and three on-track machine operators. We also explored with practitioners how those policies were created, briefed, and monitored.
We found that most defensive driving instructions were unchanged since they were introduced in the late 1990s, despite advancements in rolling stock capabilities. In the main, policies were developed without involvement from some key stakeholders, such as signalling and fleet engineers.
Signalling engineer participant in the research
We have therefore produced good practice guides to support the design, implementation, and review of PDPs. The guides aims to support operators in creating better driving policies, involving key stakeholders to make sure the way trains are driven aligns with the way the system has been designed and built to operate.
The good practice guides are now available – go to the RSSB Research Catalogue and search for T1305.
To discuss the research project, or for help with implementation, contact Marcus Carmichael, Professional Lead, Operations and Performance: Marcus.Carmichael@rssb.co.uk
