Note (to keep responses on track): I do not own a pool, nor do I have any
intention of owning a pool.

Onward: I get a nasty rash any time I spend time in an indoor pool or hot
tub, but never with outdoor pools. What's the diff? Type of chemicals used?
If the chemicals are often the same, does sunlight do something to the
chemicals in outdoor pools, making them less irritating or something?