The IP-Rating provides a classification of an instrument's protection factor from dust and water. The standard aims to provide users with more detailed information than vague terms such as "waterproof".
The format for the IP-Rating is IP XX, with each X representing an indicator number.
The first numeral indicates access to dangerous parts and protection of internal equipment. The second numeral indicates protection of internal equipment against harmful ingress of water.
First Digit: Solids (IP XX)
The first digit indicates the level of protection that the enclosure provides against access to hazardous parts (e.g., electrical conductors, moving parts) and the ingress of solid foreign objects.
Level
Object size protected against
Effective Against
0
Not Protected
No Protection against contact and ingress of objects
1
>50mm
Any large surface of the body, such as the back of the hand, but no protection against deliberate contact with body part
2
>12.5mm
Fingers or similar objects
3
>2.5mm
Tools, Thick wires, etc.
4
>1mm
Most wires, screws, etc.
5
Dust Protected
Ingress of dust is not entirely prevented, but it must not enter in sufficient quantity to interfere with the satisfactory operation of the equipment; complete protection against contact.
6
Dust Tight
No ingress of dust; complete protection against contact.
Second Digit: Liquids (IP XX)
Protection of the equipment inside the enclosure against harmful ingress of water.
Level
Object size protected against
Effective against
0
Not protected
-
1
Dripping water
Dripping watter (vertically falling drops) shall have no harmful effect.
2
Dripping water when tilted up to 15°
Vertically dripping water shall have no harmful effect when the enclosure is tilted at an angle up to 15° from its normal position
3
Spraying water
Water falling as a spray at any angle up to 60° from the vertical shall have no harmful effect
4
Splashing water
Water splashing against the enclosure from any direction shall have no harmful effect
5
Water jets
Water projected by a nozzle (6.3mm) against enclosure from any direction shall have no harmful effects.
6
Powerful water jets
Water projected in powerful jets (12.5mm nozzle) against the enclosure from any direction shall have no harmful effects.
7
Immersion up to 1m
Ingress of water in a harmful quantity shall not be possible when the enclosure is immersed in water under defined conditions of pressure and time (up to 1m of submersion).
8
Immersion beyond 1m
The equipment is suitable for continuous immersion in water under conditions which shall be specified by the manufacturer. Normally, this will mean that the equipment is hermetically sealed. However, with certain types of equipment, it can mean that water can enter but only in such a manner that it produces no harmful effects.