What is an IP Value? What do the IP Values on products mean?

IP STANDARDS developed by European Committee for Electrotechnical Standardization (CENELEC) cover the figures indicating under which conditions electrical equipments operate safely. Products are testes by manufacturing companies according to these standards, and indicated statutorily on products for consumers. The first digit of such figure indicates the ingress protection, and the second digit the protection against liquid chemicals.

For instance, if you are in such region where the environmental corrosive impact is too much, you need a fuse box not to be affected from environmental factors such as humidity, dust, and rain.  Therefore, you need to pay attention to the protection class of any product you plan to purchase.