IP stands for Ingress Protection and is a rating for enclosures of all kinds, including two-way radios. An IP rating specifies how resistant the enclosure is to foreign objects and moisture. There are two digits in an IP rating, the first represents how well the enclosure resists penetration by solid objects. Level 1 is protection against solid objects with diameter greater than 50mm. Level 6 means it is dust tight.
The second digit is for moisture penetration into the enclosure. The range is from 1 to 9. For Level 1 dripping water (vertically falling drops) will have no harmful effect. With Level 8 the equipment is suitable for continuous immersion in water under conditions specified by the manufacturer. Normally, this means 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.
