The leaded stained glass panel will have either 1/2" or poss. 3/4" zinc "U" came around it , and it will be fitted into a wood frame/door. The box to be mounted on the wall will be wood and the s.g. panel will be back-lit with fluorescent tubes. The question is - is it safe to put a leaded stained glass panel in a hospital, especially in a childrens oncology dept.
By safe do you mean that the kids could break it? Put laminated glass in front of it for easy cleaning by the hospital staff and safety against breakage.
Or are you concerned about lead poisoning? You need to i inhale or ingest lead to get lead poisoning. It's doubtful there will be a problem with this.
The zinc border will add NO additional strength to the window once it's installed, so why not use lead.