The setting
Boy Scout summer camp in the Midwest
The participants
The nature staff - no, not au naturale (that was the waterfront on the weekends), but rather the guys who showed stuff about plants and animals.

"And this boys, is poison ivy. Its not a good thing to touch it, like I just did, but its an oil that irritates and so if washed off promptly it should not be a problem."

Following this lecture on poison ivy and its makeup, how to identify it and proper avoidance of it, the nature director would go to the shower house and wash his hands.

Once, and I am certain only once, he made the mistake of going to the restroom first. Just a quick unzip and let it go and then wash hands. This was a mistake that few ever make twice. He walked funny for the next week or so. He owed a few favors to the commissary director (who assigned who-went-where) to make certain he didn't have to walk to the other end of camp.

While the above anecdote is very male oriented this can be a problem for anyone who takes a bath after coming into contact with poison ivy. As mentioned above, the irritant is an oil and will then float on the surface of the bath. As someone gets out, the oil will cling to them providing a light rash on the entire body. There are places people just don't want to itch in polite company.