Water and dust proof connectivity products are defined by their Ingress Protection (IP) numbers. The first number after IP is for the part's protection against solid objects like dust and sand. This number can range from 0, meaning no protection against dust and sand, and 6, meaning 100% protection against dust and sand.
The second number after IP is for the part's protection against liquids. It ranges from 0 to 8.
IP67 equipment is the most commonly found in the connectivity market. It is 100% protected against solid objects like dust and sand, and it has been tested to work for at least 30 minutes while under 15cm to 1m of water.
Here is a chart showing other IP ratings:
First number (Protection against solid objects)
Second number (Protection
Protected against solid objects over 50mm
(e.g. accidental touch
Protected against vertically falling drops of water
Protected against solid objects over 12mm
Protected against direct sprays up to 15o from the vertical
Protected against solid objects over 2.5mm
(e.g. tools and wires)
Protected against direct sprays up to 60o from the vertical
Protected against solid objects over 1mm
(e.g. tools, wires
and small wires)
Protected against sprays from all directions - limited ingress permitted
Protected against dust - limited ingress
(no harmful deposit)
Protected against low pressure jets if water from all directions - limited ingress permitted
Protected against strong jets of water e.g. for use on ship decks - limited ingress permitted
Protected against the effects of temporary immersion between 15cm and 1m. Duration of test 30 minutes
Protected against long periods of immersion under pressure