Environmental Protection

A truly rugged industrial device is engineered, from the ground up, to operate in the most extreme hostile environments. The industrial engineering design is not only limited to the external housing, but includes internal components, special coatings, sealants, and other design features allowing computers to be exposed to extreme humidity, dust, temperatures, vibration and shock. Included in the mix is a class of products manufactured explicitly for use in hazardous or explosive environments.

IP Ratings
IP (Ingress Protection) ratings are standards for electrical enclosures. The rating refers to the equipment's ability to permit solids and liquids to penetrate the computer's enclosure. The protection standards are defined by the IEC (International Electrotechnical Commission). A mobile computer's IP Rating is expressed as a two-digit number (Example: IP-66). The first number designates protection from solids, while the second number designates protection from liquids. Please refer to the table below for specific IP rating information.

NEMA (National Electrical Manufacturer Association)
NEMA ratings are standards that are useful in defining the types of environments in which an electrical enclosure can be used. The NEMA rating system is defined by the National Electrical Manufacturer Association, and frequently signifies a fixed enclosure's ability to withstand certain environmental conditions. Please refer to the table below for specific NEMA type designations.

NEMA ratings are rarely applied to mobile devices, and are mainly applied to fixed enclosures. For example, a NEMA rating would be applied to a fixed electrical box mounted outside, or a fixed enclosure used to house a wireless access point. Most enclosures rated for use in an outside environment include a NEMA 4 rating. NEMA ratings have more stringent testing requirements to verify protection from external ice, corrosive materials, oil immersion, dust, water, etc. These stringent testing requirements can rarely be applied to mobile devices, but there is a correlation between NEMA ratings and IP ratings. However, this correlation is limited to dust and water.

The "Comparison Table" below provides a comparison between NEMA ratings and IP ratings. It is important to realize that this comparison is only related to the protection provided against dust and moisture. For this reason, this table can only be used to convert NEMA ratings to IP ratings, but not vice versa. A few manufacturers of mobile computers will include NEMA ratings in their specifications, and it is important to understand how the NEMA specification correlates to a product's IP Rating.

MIL-STD (Military Standard) or MIL-SPEC (Military Specification)
The MIL-STD specification is a series of guidelines established by the U.S. Department of Defense in order to define specific performance and manufacturing requirements for all types of equipment. In most cases, products must be designed in accordance with the MIL-STD to be considered acceptable for use by the U.S. Department of Defense. A product's MIL-STD compliance is also a consideration for many state and local governments when purchasing mobile computers for use in public safety, emergency services, maintenance, etc.

The MIL-STD 810F standard was released on January 1, 2000 (superseded MIL-STD 810E). MIL STD 810F includes testing protocols to simulate environmental stresses from rain, humidity, salt fog, sand/dust, vibration, shock, temperature, etc. A copy of MIL-STD 810F can be downloaded from the United States Army Developmental Test Command at http://www.dtc.army.mil/publications/milstd.html.

The MIL-STD 810F standard is an all-encompassing standard that is frequently used for ruggedization testing by mobile computer manufacturers. Many manufacturers and laboratories will design their ruggedization testing in accordance to the MIL-STD 810F guidelines. However, it is important to note that when the MIL-STD 810(x) specification is listed on a product's data sheet, this usually only applies to the vibration and shock component of the standard, and does not mean that protection is included from salt fog, corrosion, rain, humidity, temperature, etc. Therefore, IP (and/or NEMA) Ratings are frequently used to signify protection from liquids and solids, and the MIL-STD is used to specify protection from shock and vibration.

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TYPE

ENCLOSURE RATING

Intended for indoor use primarily to provide a degree of protection against contact with the enclosed equipment or locations where unusual service conditions do not exist.