Downloaded from https://www.everyspec.com Fort Belvoir, VA 22060 d. CG, US Army Materiel Development and Readiness Command, The Surgeon General, The Chief of Engineers, and other commanders designated as materiel developers in AR 70-1 will— (1) Incorporate known climatic parameters in the RDTE of materiel. (2) Plan and conduct tests of materiel designed to satisfy climatic requirements (AR 70-10). (3) Recommend to the Deputy Chief of Staff for Research, Development, and Acquisition permanent sites for climatic testing of materiel in the natural environment. (4) Implement the policy regarding standard and special materiel and modification kits contained in paragraph 1- 5a.(3).
(5) Determine when severe consequences may result if the materiel fails under extreme climatic conditions and get a special study of necessary modifications of criteria in chapter 2 in such a case (c(2) above). (6) Request special studies (c(2) above) when compatibility with climatic criteria (chap. 2) is not possible or is undesirable because of the nature of the materiel or its use (e.g., operated only during winter). e.
CG, US Army Training and Doctrine Command and CG, US Army Communications Command will— (1) Include in materiel requirement document— (a) A statement of the areas or conditions in which the materiel may be operated, stored, or transported according to climatic conditions in chapter 2. (b) A description of the shelters, if any, in which the materiel will be operated. (c) A list of operational constraints (para 1-2e and f) imposed by meteorological and terrain elements other than those considered in chapter 2. (2) Request a special study when compatibility with climatic criteria in chapter 2 is not possible or is undesirable because of the nature of the materiel or its use. 1–7. Limitations.
The climatic information in chapter 2 is not to be used— a. In the RDTE of materiel to be used at a specific place or in a known limited area. This materiel should be designed to withstand climatic conditions at the specific place. In these situations, the climatic requirements should be outlined by the combat user in a special study prepared by designated Army environmental specialists (para 1-6c(2)). b. In the RDTE of materiel that has inherent limitations, such as food items or medical supplies that must always be kept in controlled environments.
Also excluded are most individual clothing items, which, by themselves, are not capable of protecting the soldier from a wide range of climatic conditions. The total range of climatic conditions cited in chapter 2, however, can and should be used as the guide for developing the required number of clothing ensembles to protect personnel against all conditions they may encounter. c. To authorize the issue of materiel. 1–8. Application of design values. The general design values in chapter 2 represent a conservative design approach; that is, there is little risk that the design values will be exceeded in the areas to which they apply.
Because there is some risk, the design values should be modified for some materiel items. In certain cases, failure of an item may be so critical that more severe climatic criteria should be applied to ensure against environment-related failure. In other cases, the consequences of failure may be slight, so that the cost of designing to the given values may be unwarranted. Special study may be required in these cases to determine the most appropriate design values (1-6c(3)). The type of failure is also an important consideration. Two categories of failure that may cause different design decisions are identified as follows: a. Reversible failure.
For the duration of climatic extremes, the materiel may continue to function, but its perform- ance or safety is reduced, or it may cease to function. When the extreme climatic conditions cease, the materiel will return to normal function. b. Irreversible failure. The materiel suffers a failure so damaging during climatic extremes that it will not return to normal function when the extreme climatic conditions cease. 1–9. Climatic testing. Materiel under development is always tested in climatic chambers and usually undergoes additional natural (or field) environmental tests. a. Chamber climatic test. (1) Simulated climatic tests.
The use of simulated climatic tests is encouraged, especially under combined (e.g., temperature and humidity) and sequential conditions, that supports efforts aimed at better simulation through improved test procedures and facilities. In certain cases, it will not be practical or necessary to duplicate exact conditions of the applicable climatic design values in these tests. The materiel, however, will be tested to meet the guidelines of the requirements document. Developers doing simulated climatic tests will use the daily cycles normally found in nature as their models, rather than chamber testing only at the extreme condition.
This daily cycling gives more realistic moisture 5 AR 70–38 • 15 September 1979