Omega

I am an electrical engineer working with a large railway engine manufacturer in India. My work frequently involves traveling inside an electric engine cab to inspect the dashboard's instruments. I do not go near any of the electrical motors of the engine,... 

and rely on the Railmaster instead, which if I remember correctly was built to withstand the effect of magnetic fields. Other watches with high antimagnetic capabilities are the IWC Ingenieur (they have a chrono version as well) and the Rolex Milgauss. So...