Research ready to use
Fairer colour vision testingMobile devices to help drivers safely perform their dutiesTaking a fresh look at legacy rules
A new two-step approach allows people who would currently fail to take on safety-critical roles.
Being able to see and distinguish colours is an important requirement for many safety-critical roles on the railway, especially in terms of lineside signalling. The standard Ishihara test is commonly used to screen for colour vision deficiency in rail.
Most people will have undertaken the Ishihara test at some point in their life. It consists of a plate with different-coloured dots, and you have to identify the number that is shown.
However, the Ishihara test is something of a blunt instrument. It detects that somebody may have colour-deficient vision, but not the specific degree. Potential rail employees with minor colour deficiency may fail the test, even though they could safely perform the role they are being assessed for.
Current medical standards allow for a secondary test should somebody fail the Ishihara test. However, there is no guidance on the criteria for a pass or fail.
Our research, delivered by City University, proposes a two-step approach to colour vision assessment. The Ishihara test would be the primary screening test, with 100% correct answers needed to pass. But anyone who fails can take a Colour Assessment and Diagnosis (CAD) test to determine the specific degree of their colour vision deficiency.
The research defined pass or fail thresholds that exclude only those with colour deficiency that would impair their ability to perform the role safely. Statistical analysis suggests that the proposed approach will enable a significant number of people who currently fail the Ishihara test to be assessed as safe to perform the role.
The findings of this research have informed changes to rail industry standard RIS-3789-TOM. The revised standard is currently out for consultation and will be published in March 2025.
‘This is a great piece of research and could make such a difference for people’s careers in rail.’
Read the research findings at rssb.co.uk/research-catalogue/CatalogueItem/T1279.
For support with the changes to colour vision testing, contact Marcus Carmichael, Professional Lead, Operations and Performance:
Marcus.Carmichael@rssb.co.uk
New guidance helps operators identify the right technology for the driving cab.
Passenger and freight operators are increasingly issuing their train drivers with mobile electronics, such as phones, tablets, or other devices. The aim is to reduce the number of paper publications and forms that drivers deal with.
Currently, there are no industry-wide standards for such devices. Our research established the tasks that drivers are currently carrying out with mobile electronic devices and other ways that devices might support driving in future.
For each of these use cases, we defined the minimum functional and ergonomic requirements a mobile device should meet. The guidance will help operators specify suitable devices for the task they are looking to support. This will reduce the risks and promote a common approach across the industry.
Download the guidance at rssb.co.uk/research-catalogue/CatalogueItem/T1332.
To discuss the findings, contact Marcus Carmichael, Professional Lead, Operations and Performance:
We reviewed the requirements for clearances to allow for opening windows.
In the past, many train carriages had opening windows or doors operated from outside. Because of this, rules specify 450 mm of additional space between rolling stock and structures.
Vehicles have been progressively replaced with modern rolling stock, with fixed windows and power doors. But regulations still specify additional space—known as window box clearances—between rolling stock and structures. This can cause significant extra costs when altering old structures that predate these requirements. Our research looked at whether window box clearances are still needed in today’s railway.
We assessed the clearance of 279,898 structures on the network. Of these, 4,785 did not provide sufficient space.
The risk of a person being struck when leaning out of a window is far lower than 30 years ago. However, it still exists on older rolling stock. The Office of Rail and Road (ORR) mandated the removal or mitigation of passenger-operated windows by March 2023, but this requirement has yet to be fully met. Until it is, the passenger window box requirement cannot be withdrawn.
However, based on the potential safety risk posed by non-compliant structures, the research calculated a threshold value of £100,000. Above this amount, complying with the window box clearance requirements may not be economically viable. This figure can be used during cost-benefit analysis of infrastructure works.
Read more about the findings at rssb.co.uk/research-catalogue/CatalogueItem/T1329.
The output of this research can help with standard deviations. It has also led to a change in the Sectional Appendices, highlighting the importance of a safe system of work for train operators where passengers can lean out of windows. To discuss the research, contact Paul Gray, Professional Lead, Engineering:
Paul.Gray@rssb.co.uk
