How Are Human Factors Included in Standards?

Standards provide a blueprint for tried-and-tested processes. They need to be usable, as does the technology and equipment. Human factors expertise helps us understand the relationship between people and technology and equipment. This is important because sometimes people don’t quite use equipment in the way intended, or the addition of a new piece of equipment to an existing situation has unintended effects. Human factors experts can identify where this is happening and recommend better ways forward, as well as understanding what it is that the people doing a particular job really need to know to do that job well. While human factors may not always be the driving force behind the development of a new standard, including it is essential to ensure standards and processes play to people’s strengths. 

Human factors experts have an overview of all standards developed or revised at RSSB, and get involved in the detailed work when they see their input is needed. Once the standards are developed or revised, the human factors expertise may not be immediately apparent, but it is there. For instance, the standard for Train Protection Warning Systems (TPWS), RIS-0775-CCS Issue 3, includes clear statements about the nature of the driver-machine interface and the minimum requirements for safety and ease of operation even after retrofitting TPWS. These requirements mean that the equipment design is optimised for the human interface and is unlikely to be misused or misunderstood.

There are also some examples where human factors expertise is more readily apparent, such as the standards for car stop markers. The design and positioning of car stop markers needed to be addressed because of the high numbers of signs that were installed on some platforms, with potential safety risks if these are misunderstood leading to trains stopping in the wrong place and doors being released beyond the end of the platform. Presenting lots of information means that drivers may not be able to interpret it all correctly in the time available; human factors expertise was necessary to revise and improve requirements.

Human factors expertise has also been used to support the publication of the Rule Book app. The app contains all the relevant parts of the Rule Book and is presented in a form optimised for mobile devices. It includes the opportunity for users to make notes and critically, it updates automatically, normally in March or September with revised rules that then come into effect three months later. The Rule Book app also enables organisations to manage updates more easily. Human factors expertise has also helped with the app’s layout and functionality.
The users of standards can therefore be reassured that they have been developed to all aspects of making a better, safer, railway, including knowing that the standards have been optimised for the humans that will operate the equipment and processes in the railway system.