I was about to suggest looking at the washi film site but you obviously got there before me. It will probably help to wait and see what you end up with. Once you know the brand, more information might be easier bto find.
It'll probably be an orthochromatic film safe to handle under red light though and I imagine it should be stored just like any other film, unless you have x-rays flying about in which case you'll need a lead lined box.
And if you have any spare, don't hesitate to get in touch! :-D