Waterproof grade adopt from IEC60529,it is different in various application. Check below introduction.

According to standard,’X X ’ is double digits,the first one means protect level to solid,the second one refers to protect level to liquid.

There are 7 levels for solid resist ,indicate from 0~6,while 9 levels for liquid resist ,indicate from 0~8.
IPX0: without protection
IPX1:Vertically falling drops shall have no harmful effects
IPX2:Vertically falling drops shall have no

harmful effects when the enclosure is tilted at any angle up to 15” on either side of the vertical
IPX3:Water sprayed at an angle up to 60° on either side of the vertical shall have no harmful effects
IPX4:Water splashed against the enclosure from any direction shall have no harmful effects
IPX5:Water projected in jets against the

enclosure from any direction shall have no harmful effects
IPX6:Water projected in jets against the

enclosure from any direction shall have no harmful effects
IPX7:Ingress of water in quantities causing harmful effects shall not be possible when the enclosure is temporarily

immersed in water under standardized conditions of pressure and time (1m)
IPX8:Ingress of water in quantities causing harmful effects shall not be possible when the enclosure is continuously immersed in water under conditions which shall be agreed between

manufacturer and user but which are more severe than for numeral 7
IPX9K:High pressure water jet test (nozzles inner diameter 12.5mm，water temperature 80±5℃)