Occasionally, you'll hear people referring to 'rash vests' or 'rash guards'. These are relatively new, but they are a good thing, and you may want to look at them if you spend a lot of time in the sun or like snorkelling off boats.

Rash vests were developed in Australia for surfers, who wanted to wear something to stop themselves getting a rash when they levered themselves onto their surfboards. It was too hot to wear a wetsuit, so they developed colourful spandex and polyester tops that did the job. As it was Australia, and they know something about sunburn, the new shirts blocked a lot of the sun's UV rays - which made it ideal for children. That explains why a lot of beach shots in Australia show kids clothed top to toe in colourful material - it's a defence against the sun.

Other sports took up rash vests too. Snorkellers wear them when they know they're going to be in the sun or on a boat, because they are good at blocking solar radiation and they dry quickly. They're lighter and easier than a wetsuit, especially when it's hot. They may offer a small protection against jellyfish, especially if they're long sleeved. Steve has a rash vest, but he wears his because he thinks it makes him look macho. 

So they're worth looking at. A newer development is the 'swim shirt' that is looser fitting, but does the same job.