The United States Military Standard referred to as MIL-STD-810, "Department of Defense Test Method Standard for Environmental Engineering Considerations and Laboratory Tests" emphasizes tailoring an equipment's environmental design and test limits to the conditions that it will experience throughout its service life, and establishing chamber test methods that replicate the effects of environments on the equipment rather than imitating the environments themselves. The MIL-STD-810 test series are approved for use by all departments and agencies of the United States Department of Defense (DoD). Although prepared specifically for DoD applications, the standard may be tailored for commercial applications as well.
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The military standard MIL-STD-810 test series addresses a broad range of environmental conditions that include: low pressure for altitude testing; exposure to high and low temperatures plus temperature shock (both operating and in storage); rain (including wind blown and freezing rain); humidity, fungus, salt fog for rust testing; sand and dust exposure; explosive atmosphere; leakage; acceleration; shock and transport shock (i.e., triangle/sine/square wave shocks); gunfire vibration; and random vibration. The environmental management and engineering processes described within MIL-STD-810 can be of enormous value to generate confidence in the environmental worthiness and overall durability of a system design. Still, there are limitations inherent in laboratory testing that make it imperative to use proper engineering judgment to extrapolate laboratory results to results that may be obtained under actual service conditions. In many cases, real-world environmental stresses (singularly or in combination) cannot be duplicated in test laboratories. Therefore, users should not assume that a system or component that passes laboratory testing also would pass field/fleet verification trials.
The military standard MIL-STD-810 series of test methods are issued by the United States Army's Developmental Test Command who is chartered under the Defense Standardization Program (DSP) with maintaining the functional expertise and serving as the DoD-wide technical focal point for the standard. The current document revision (2009) is Revision G (i.e. MIL-STD-810G) which was issued on October 31, 2008. It superseded Revision F (MIL-STD 810F) released on January 1, 2000 and which was last updated on May 5, 2003.
The Institute of Environmental Sciences and Technology (IEST) published The History and Rationale of MIL-STD-810 which captures the thought process behind the evolution of MIL-STD-810. It also provides a development history of test methods, rationale for many procedural changes, tailoring guidance for many test procedures, and insight into the future direction of the standard. In 1965, the United States Air Force (USAF) released a technical report entitled "AFFDL-TR-65-197 - The Evolution of USAF Environmental Testing" that presents supporting information on the origination and development of natural and induced environmental test for USAF aerospace and ground equipment. The MIL-STD-810 test series originally addressed generic laboratory environmental testing, but with Revision D, started to focus more on shock and vibration tests that closely mirrored real-world operating environments. Revision F further defined test methods while continuing the concept of creating test chambers that simulate conditions likely to be encountered during a product's useful life rather than simply replicating the actual environments. More recently, Revision G implements Test Method 527 that calls for the use of multiple vibration exciters to perform simultaneous multi-axis shaking to simultaneously excite all test article resonances and simulate real-world vibrations. This approach replaces the present three tests: shaking a load first in its x axis, then its y axis, and finally in its z axis.
The MIL-STD-810 test series contains environmental laboratory test methods that are applied using specific test tailoring guidelines described within the standard. Note that test methods are not to be called out in a "blanket" fashion nor applied as unalterable routines, but are to be selected and tailored to generate the most relevant test data possible, and incorporated into a system's final design specification, as specified by the Procuring Agency. The selected test methods are designed to simulate specific environmental conditions anticipated to be encountered over the life of the system.
Specific examples of Test Methods (where the older MIL-STD-810F is used as an example) are listed below:
Claiming "compliance to MIL-STD-810" can be misleading; as it is a flexible standard with no authority to certify or oversee it that allows commercial suppliers to make up their own test methods to fit their product. Suppliers can and some do take significant latitude with how they test their products, as well as how they report the test results. As a result, claims of "compliance with MIL-STD-810" can be misleading. When queried many manufacturers admit no testing has actually been done and that the product is merely designed/engineered/built-to comply with the standard. This is because many of the tests described are very expensive to perform and require special facilities. Further if some testing was actually done they would have to specify: