IP protection

The IP protection index includes 2 digits. it represents the degree of protection provided by enclosures

the first digit represents the protection against solids (dust)
the second digit represents the protection against liquid

	First digit - solids	Second digit - liquids
0	no protection	no protection
1	Protection against solids over 50 mm in size	Protection against water drops falling vertically on a product in normal position
2	Protection against solids over 12 mm in size	Protection against water drops falling on a product with up to 15° inclination with vertical of his normal position
3	Protection against solids over 2.5 mm in size	Protection against water drops falling on a product with up to 60° inclination with vertical of his normal position
4	Protection against solids over 1 mm in size	Protection against water drops falling on a product in any direction
5	Dust protected	Protection against water jets in any direction
6	Dust proof	Protection against powerful water jets in any direction
7		Protection against temporary immersion
8		Protection against long term immersion

Refer to IEC (international Electrotechnical Commission) number IEC 60529, for more details www.iec.ch
NEMA is a US standard. NEMA stands for National Electrical Manufacturers Association.
An approximate correlation between NEMA and IP for water and dust is the following:

IP52	IP54	IP56
NEMA 12	NEMA 13	NEMA 4 & 4X

IP focuses on water and dust
NEMA comprises more topics such are rust.
Refer to the site www.nema.org, standard 250 for more informations