For any equipment installed outdoors and exposed to dust and rain, the first question is whether its enclosure can keep those elements out. This is precisely what the Ingress Protection (IP) rating quantifies, so it must be examined first when selecting an LED driver for such a location.

An IP rating is written as IP followed by two digits, IP[X][Y]:

• First digit (X) — protection against solid particles, from 0 (no protection) up to 6 (fully dust-tight).
• Second digit (Y) — protection against water, from 0 (none) through 5 (low-pressure water jets), 6 (powerful jets), up to higher levels for immersion.

For an outdoor display facing dust and rain, a driver of at least IP65 (dust-tight and protected against water jets) is generally required so the environment cannot damage the electronics.

The other specifications matter for performance but not for survival in the environment: dimming compatibility concerns brightness control, power factor rating concerns how efficiently the driver draws current from the mains, and output current tolerance concerns how accurately it drives the LEDs. All of these are irrelevant if moisture or dust destroys the driver first, which is why the IP rating is the primary environmental check.