The HTC 10 has an IP53 rating that guarantees that the phone will be protected from dust getting into its vital components and for spraying water for up to five minutes. The way devices get tested for that rating is vigorous and, while not government-regulated, is pretty important to the International Electrotechnical Commission.
What does this practically mean? Well, we wouldn’t encourage you to use your HTC 10, Pixel or Pixel XL in the rain, directly in the path of a hose’s or water cannon’s spray or not in the pool. But at least you should be able to keep using your device to full working satisfaction if your phone is exposed to the first few conditions. Definitely not the last, especially for more than a minute or two (as unofficial dunk tests have previously shown us) — though we sometimes wonder if maybe these OEMs are being just a tad too conservative.
Source: Android Police