The International Protection Rating's function is to provide consumers with an accurate understanding of how resilient electronic devices are to both solids and liquids -- preventing companies from making inaccurate claims about their products' protection levels.
Rating System for Solids
A rating consists of two numbers following the letters IP. The first number represents the protection against solid items, the second number against liquid. For solids the ranking is between zero and six, with zero meaning the device offers no protection against the intrusion of objects and a six offering complete protection against dust.
Rating System for Liquids
For liquid the scheme runs from zero to eight; a zero means no protection is offered while an eight means the item can be immersed in water because it is protected against long periods of immersion under pressure.