For sure, it does not need to be in the "skills shortage occupation" e.g Rail Engineer, Structural/bridge engineers, Transportation and highways engineers, Ground Engineering, but it must be in the graduate level position.
If you got degree in electrical engineering you could work as a railways engineer doing Signaling, Communications, Power Supply, and other Electrification parts of railway system.
You could also work as Structural/bridge engineers doing Building Services Engineer. Have a look in the following website, the explanation of Engineering Shortage Occupations.
http://www.hsmp-services.co.uk/engineering_sector.html
Pantaiema