An IP rating is shorthand for an Ingress Protection mark; usually a two-digit grading system that is applied to the enclosure of a mechanical or electrical item.
This gives customers a clear indication of the item’s resistance to various types of unwanted intrusion and defines the different levels of sealing effectiveness against foreign bodies (tools, dirt, etc) and moisture.
The numbers that follow IP each have a specific meaning. The first digit indicates the degree of protection from solid objects. The second defines the protection level from various forms of moisture (drips, sprays, submersion, etc).
The reason for having a universal IP rating system is so that buyers and users can be confident of how safe it is to use certain electrical or mechanical goods in certain environments and applications.
More vague marketing terms such as ‘waterproof’ don’t necessarily give a clear definition of precisely where and to what extent an item can resist moisture ingress. An IP rating is designed to provide a far more specific account.
The first digit will be a number between 0-6 and indicates the degree of protection from ingress of solid objects (the user themselves, and other potentially harmful particulates such as dust or dirt).
The second digit will be a number between 0-9, denoting the quality of resistance to moisture ingress at varying intensities, angles, depths and pressures of exposure or immersion.
In some cases, an additional letter may be added to the end of IP Ratings, to indicate either certified resistance to hazards such as oil or high voltages, or a scenario in which the testing was conducted, e.g. moving water.
The tables below tell you what each digit in a standard IP code means.