Using an onsen with a stoma

Is it possible to use an onsen if you have a stoma & bag?
What would be the ettiquette? eg covering the bag or using a waterproof plaster over the stoma.

I apologize in advance if I accidentally say something insensitive here...

I was reading through blogs by different ostomates, and some are writing about visiting hot springs - one mentioned a big plaster to cover the stoma, or a small bag (to be replaced after taking your bath). But they do mention it as a small adventure, alongside other comments that they are finding more and more bathroom facilities with one for ostomates, meaning, the society at large becoming more friendly to ostomates.
(Sorry the other day I noticed a different basin in one of the toilets on a Shinkansen train, and I did not quite understand what it was for...now I know.. so much to learn... )

The last photo on this page depicts bags for use while bathing (the size differs slightly depending on the size of the stoma), and the "square" in the photo is like a huge bandage to cover over the stoma.
http://orangemikann.cocolog-nifty.com/blog/2007/06/post_ee06.html

This is a manufacturer who makes a waterproof cover over a folded-up bag.
http://homepage2.nifty.com/my-care/top.html

There seem to be some websites listing "stoma friendly/accommodating" hot springs - probably meaning they have separated dressing rooms and bathrooms.

According to the recommendation by Japan Ostomy Association, Inc., they say:
http://www.joa-net.org/contents/useful/05_04.htm

"6. In public bathing facilities, wear a less conspicious skin-colored mini stoma bag, or wear an empty bag rolled up and fixed to your skin with surgical tape so that it does not stand out.
In the washing area, if you have a stoma on your left side, take a seat at the left end, and if your stoma is on the right take a seat at the right end,so that you would not have to worry about others washing next to you. It would be safer to take a bath before a meal, and be sure to bring your stoma appliance to the bath just in case."

Under "traveling," they also mention "if bathing in a spring water with sulfur content, be careful not to let the water come in contact with your stoma."

http://www.joa-net.org/contents2/sponsor_en/index.htm
"ALCARE" mentioned here seems to be the one producing the plaster and the mini bag.

Many thanks, that's fantastic info. No insensitivity at all.
When you're dealing with this sort of issue I think one has to be matter of fact.

I'm in the UK but travel to Japan to visit family. As I'm expecting to become an ostomate soon I had wondered if onsens would be off the agenda.

Glad to hear of the appropriate etiquette. If needbe I can look out for suitable supplies in the UK to take with me.