IP Ratings (Ingress Protection) Rating for Equipment and Enclosures

A three-digit number established by the International Electrotechnical Commission, is used to provide an IP Rating to a piece of electronic equipment or to an enclosure for electronic equipment. The IP code indicates the level, or amount of the protection.

The three digits represent three different forms of environmental influence:

The first digit represents protection against ingress of solid objects.
The second digit represents protection against ingress of liquids.
The third digit represents protection against mechanical impact damage.

(*The third digit is often omitted, resulting in a 2-digit IP Rating covering ingress against solid objects and liquids only).

The larger the value of each digit, the greater the protection from that influence. As an example, a product rated as IP573 would be better protected against environmental factors than another similar product that was only rated as IP432.

IP TABLE

NEMA

NEMA stands for the National Electrical Manufacturers Association. They provide a forum for the standardization of electrical equipment, enabling consumers to select from a range of safe, effective, and compatible electrical products. The organization has also made numerous contributions to the electrical industry by shaping public policy development and operating as a central confidential agency for gathering, compiling, and analyzing market statistics and economics data.

Environmental ratings for enclosures based on "NEMA" Type designations

Conversion of "NEMA" Type to "IP" Code designations*

MIL-STD (Military Standard) or MIL SPEC (Military Specification)

Is a series of performance and manufacturing guidelines set by the US Department of Defense for military and commercial equipment and applications. These guidelines specify allowable parts and environmental condition ranges that a tool or other device must be able to operate in to meet compliance.

MIL-STD 810 E and F are generally accepted as the highest standard for ruggedized testing by mobile computer manufacturers.

MIL-STD 810 test method is used to generate confidence in the environmental worthiness and overall durability of material system design. The testing process follows guidelines which include program documentation, program roles, test standards and laboratory test method guidelines for all categories. The laboratory test methods are broken down into 24 categories. The required compliance test categories include:

Before testing can begin, the item has to have environmental exposure, which means that the test item is run under standard ambient conditions to ensure the item is operating properly and to ensure pretest baseline performance data is collected.

The actual tests are carried out according to pre-defined test plans and criteria. The tests can be laboratory or natural environment field tests, or a combination, which ever applies. The test procedure is dependent on the environment tested. The procedure(s) and its execution provide the basis for collecting the necessary information.

After completion of each environmental test, the post-test data is examined and recorded in accordance with material specifications and program guidelines. The results are compared with the pre-test data. The post test record includes: test sequence used, deviations from planned test program, performance data, test conditions and a signature of the test team, to name a few. A final test report will be created for each test which includes an analysis of the test results.

You may notice some products will carry a MIL-STD 810E rating and some may state they are MIL-STD 810F compliant. MIL-STD 810F is a revision of MIL-STD 810E. The tests and methods are basically the same but much of the standard has been rewritten to provide clearer direction. Many of the changes that can be found with the MIL-STD 810F are minor or administrative in nature, but technical changes and improvements can be found throughout (i.e. additional technical testing guidelines).

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IS (Intrinsic Safety)

IS is a term representing the Hazardous Location classifications as described in the National Fire Protection Association’s (NFPA) National Electrical Code (Article 500). The National Electrical Code (NEC) defines Hazardous Locations as those areas “where fire or explosion hazards may exist due to flammable gases or vapors, flammable liquids, combustible dust, or ignitable fibers or flyings.”

An intrinsic safety rating details the specific Hazardous Location in which an electrical device can be used without fear of electrostatic discharge that may cause an explosion.

SUMMARY OF CLASS I, II, III HAZARDOUS LOCATIONS