I'm doing an investigation about building a bridge over a railway line and its catenary system. I'm mainly interested in the electromagnetic environment on the bridge as it is affected by the presence of the catenary.
Is this an issue that I need to be concerned with?
I have no experience in either of these fields and that is exactly why I would like to get insight from people who do work in these particular fields. To answer some of the questions that have been raised in the comments section:
What order of distance, what voltage? AC/DC? | South Africa or ...? | I'd expect regulatory requirements for unrelated reasons would place you well outside EM interaction range.
Ideally I would like the bridge to be of reasonable height such that the pedestrians wouldn't mind taking the stairs. I have freedom to reduce the height of the catenary system for exactly this reason. It is a 25 kV AC catenary system. What is the standard EM interaction range?
What electromagnetic enviroment? You haven't specified any. Will this bridge parallel a power line? Be near a large radio transmitter? What makes you think there are electromagnetic issues here at all?
According to this Wikipedia article, AC high voltage lines "give off" electromagnetic radiation. The bridge is not close to anything really (no power line or large radio transmitter), it just goes over the train track and its catenary.