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Ingress Protection

What does IP stand for?
IP is an acronym for Ingress Protection

Why is Ingress Protection Important?
Liquid and/or solid particle ingress into electrical equipment may not only be harmful to the equipment, it may also be dangerous to the operator. Therefore when buying electrical equipment whether it be an electric motor, a light fiiting or an enclosure, it is essential to know what degree of ingress protection the item offers.

So how is Ingress Protection quoted?
An "IP" number, or as it is commonly known, an IP rating is used to specify the environmental protection offered. The IP rating is composed of two numbers, the first referring to the protection against solid object ingress and the second against liquid ingress. The higher the number the better the protection.

Are there standards covering these ratings?
The applicable European standards for ingress protection are:
- BS EN 60529 Specification of Degrees of Protection Provided by Enclosures
- IEC 529 Specification of Degrees of Protection Provided by Enclosures

What are the numerical codes?

Ingress Protection Classification
First Number		Second Number
IP	Protection Provided	IP	Protection Provided
0	No Protection	0	No Protection
1	Protected against solid objects up to 50mm e.g. accidental touch by hands	1	Protected against vertically falling drops of water e.g. condensation
2	Protected against solid objects up to 12mm e.g. fingers	2	Protected against direct sprays of water up to 15 deg from the vertical
3	Protected against solid objects over 2.5mm e.g. tools	3	Protected against direct sprays of water up to 60 deg from the vertical
4	Protected against solid objects over 1mm e.g. wires	4	Protected against water sprayed from all directions - limited ingress permitted
5	Protected against dust - limited ingress (no harmful deposit)	5	Protected against low pressure jets of water from all directions - limited ingress permitted
6	Totally protected against dust	6	Protected against strong jets of water e.g. for use on shipdecks - limited ingress permitted
		7	Protected against the affects of immersion between 15cm and 1m
		8	Protected against long periods of immersion under pressure

What do they use outside Europe?
In North America, the NEMA classification is used. NEMA (National Electrical Manufacturers Association) is a US trade association representing the interests of electroindustry manufacturers of products used in the generation, transmission and distribution, control, and end-use of electricity.

How does the IP and NEMA systems compare?
The IEC and NEMA degrees of protection can not be fully compared as equivalent ratings. The NEMA Standard includes tests for environmental conditions such as mechanical damage, corrosion, rusting, ice formation, etc. However the follwoing table can be used as a guide:

NEMA Enclosure Type Number	IEC Classification
1	IP 10
2	IP 11
3	IP 54
3R	IP 14
3S	IP 54
4 and 4X	IP 56
5	IP 52
6 and 6P	IP 67

Does NEMA produce standards?
NEMA Standard Publication 250 and UL 40 Standard Publication both provide further information on ingress protection ratings used in the US.