i think noone gets hurt from beeing “in” the light. But everyone gets hurt from looking into the source.
You should know this, if you name your company “intolight” (just kidding homie:)
So nope - the sun is not dangerous - but if you look into the sun for to long - you are just blind! Same with a projector!
anyway - from my experience this problem appears if the director and the projector are on similar height, working in a classical “theatre black box” (this is very different to normal light conditions and sunny environments)
If the director communicates with the actor facing him (and the projector) while his pupils are wide open because of his dark environment - and you do this for two month…then your actor WILL be hurt - mentally and physically.
For rehearsal : Projector up - Director down…turn on lights whenever possible.
For performance: you can put the projector wherever you think is best)
I dont want to sound mean: but i recommend trying for yourself. If you look into a 6k projector from 8m distance - in a dark room - then you will not feel comfortable - because your body wants to tell you something. Sorry brother ; Hope your performer gets better and you guys succeed with your show.