Have a rinsing facility immediately at hand, such as the rinsing hose you are going to need anyway, and some kind of emergency eyewash bottle. Slight splashes onto the skin are immediately uncomfortable, but a quick rinse will take care of them. I have been amused watching the professional ...
An above-water system provides automatic alerting for possible drowning victims in swimming pools or the like. One or more electro-optical sensors are placed above the pool surface.