Epilepsy is inherently dangerous condition to have. If you have a seizure, and nobody is around, you could hit your head and die before anyone helps you. Or you could be injured by your environment or objects in your possession.

Seizures also have what's called a postictal phase, which essentially lingering side effects that vary greatly from person to person.

The danger that this individual bears some responsibility to mitigate manifests when there is gap between the knowledge/expectations of co-workers and the intentions of the individual. I would not be surprised if her determination to push her limits has resulted in medical incidents that could have been avoided.