The IP 'Ingress Protection' rating system provides a means of classifying the Degrees of protection from dust and water afforded by electrical equipment and enclosures. The system is recognised in most countries and is set out in BS EN60529 1992 Degrees of protection.

First Number Protection Against Solids				Second Number Protection Against Liquids
IP		Test		IP		Test
0		No protection		0		No protection
1		Protection against solid objects over 50mm e.g.. accidental touch by hands		1		Protected against vertically falling drops of water
2		Protection against solid objects over 12mm e.g.. fingers		2		Protected against direct sprays of water up to 15° from the vertical
3		Protection against solid objects over 2.5mm[tools & wires]		3		Protection against sprays 60° from the vertical
4		Protection against solid objects over 1mm [tools, wires & small wires]		4		Protection against water sprayed from all directions - limited Ingress permitted
5		Protection against dust - limited Ingress [no harmful deposit]		5		Protection against low pressure jets of water sprayed from all directions - limited Ingress permitted
6		Totally protected against dust		6		Protection against strong pressure jets of water e.g.. for use on shipdecks - limited Ingress permitted
				7		Protection against the effects of temporary immersion between 15cm and 1m. Duration of test 30 minutes
				8		Protection against long periods of immersion under pressure
				9K		Protection against steam jet cleaning