Danger to others at work

I had a seizure while working in april. My employer required a 'fitness for duty' letter to allow me to return.

I went to an epilepsy neurologist.The doctor increased my lamictal dosage and recommended I wait 3 months.

At the end of July, that neurologist gave me a 'fitness for duty' letter with no work restrictions. My employer didn't accept it. I went to a occupational doctor for another assesment and was told I was ok and that doctor gave me another equal letter.

I'm predicting they will say I am a danger to others at work. I don't have a desk job. What are the laws about this aspect? I can't find anything.

Any help is appreciated!