IPX7 Ingress of water in harmful quantity shall not be possible when the enclosure is immersed in water under defined conditions of pressure and time (up to 1 meter (3 ft 3 in) of submersion).

IPX8 The equipment is suitable for continuous immersion in water under conditions which the manufacturer shall specify. However, with certain types of equipment, it can mean that water can enter but only so that it produces no harmful effects. The test depth and duration are expected to be greater than the requirements for IPx7, and other environmental effects may be added, such as temperature cycling before immersion.

IPX9 Protected against close-range high-pressure, high-temperature spray downs.

Smaller specimens rotate slowly on a turntable from 4 specific angles. Larger specimens are mounted in the intended position when used, no turntable required, and are tested freehand for at least 3 minutes at a distance of 0.15–0.2 meters (5.9 in – 7.9 in).

The specific requirements for the test nozzle are shown in figures 7, 8, & 9 of IEC (or EN) 60529.

This test is identified as IPx9 in IEC 60529.