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Specifications and Standards


Alternate Definition

A defense specification (often referred to as a "MIL-SPEC") refers to a document that describes the essential technical requirements for purchased materiel that is military-unique or substantially modifed commercial items. Should a material, product, or service fail to meet one or more of the applicable specifications, it may be referred to as being out of specification. 

A defense standard (often refered to as a "MIL-STD") is a document that establishes uniform engineering and technical requirements for military-unique or substantially modified commercial processes, procedures, practices, and methods. There are six types of defense standards: data standards, interface standards, design criteria standards, manufacturing process standards, standard practices, and test method standards.  US defense standards are used to help achieve standardization objectives by the DoD. Standardization is beneficial in achieving interoperability, ensuring products meet certain requirements, commonality, reliability, total cost of ownership, compatibility with logistics systems, and similar defense-related objectives.

Alternate Definition Source

DoD Manual (DoDM) 4120.24Defense Standardization Program Procedures

MIL-STD 961DDefense and Program-Unique Specifications Format and Content

MIL-STD-962Defense Standards Format and Content

General Information

Military Specifications (MIL-SPEC)

As defined above, a MIL-SPEC is a document that describes the essential technical requirements for purchased material that is military unique or substantially modified commercial items. Sometimes the term specification is used in connection with a data sheet (or "spec" sheet). A data sheet is usually used for technical communication to describe technical characteristics of an item or product. It can be published by a manufacturer to help people choose products or to help use the products. A data sheet is not a technical specification. MIL-STD 961D establishes the format and content requirements for defense specifications and program-unique specifications prepared either by DoD activities or by contractors for the DoD.

There are three major types of defense specifications:

  1. Performance Specifications - A performance specification states requirements in terms of the required results with criteria for verifying compliance, but without stating the methods for achieving the required results. A performance specification defines the functional requirements for the item, the environment in which it must operate, and interface and interchangeability characteristics.
  2. System Performance Specifications - State the system level functional and performance requirements, interfaces, adaptation requirements, security and privacy requirements, computer resource requirements, design constraints (including software architecture, data standards, and programming language), software support and precedence requirements, and developmental test requirements for a given system.
  3. Detailed Specifications - Detailed specifications specify requirements in terms of material to be used; how a requirement is to be achieved; and how a product is to be assembled, integrated, fabricated or constructed. Applicable to development of contractor final design drawings as well as items being built, coded, purchased, or reused.


Military Standards (MIL-STD)

MIL-STDs document uniform technical requirements for military-unique or substantially modified commercial processes, procedures, practices, and methods. There six major types of defense standards are as follows: 

  1. Data Standards  -  are documented agreements on representations, formats, and definitions of common data which improve the quality and share-ability of environmental data by: increasing data compatibility and improving the consistency and efficiency of data collection.
  2. Interface Standards - specify the physical, functional, or military operational environment interface characteristics of systems, subsystems, equipment, assemblies, components, items, or parts to permit interchangeability, interconnection, interoperability, compatibility, or communications. Non-Government standards should be used to the extent possible to specify interface requirements. DoD interface standards should only be developed to specify military-unique interface requirements. DoD interface standards may be cited as solicitation requirements without need for a waiver by the Milestone Decision Authority.
  3. Design Criteria Standards - are developed to specify military-unique design or functional criteria that must be adhered to in the development of systems, subsystems, equipment, assemblies, components, items, or parts. These design criteria are not primarily related to requirements that affect interchangeability, interoperability, interconnection, compatibility, or communications. Adherence to these design criteria standards, however, will affect the manufacturing of a product.
  4. Manufacturing Process Standards - state the desired outcome of manufacturing processes or specifies procedures or criteria on how to perform manufacturing processes. The DoD discourages the development of manufacturing process standards. A DoD manufacturing process standard requires the Milestone Decision Authority’s waiver to be cited as a solicitation requirement.
  5. Standard Practices - are developed when it is necessary to specify procedures on how to conduct non-manufacturing functions. Standard practices should only be developed for functions that, at least some of the time, are obtained via contract from commercial firms. Procedures for functions performed only by DoD personnel should be covered by such documents as regulations, directives, instructions, technical manuals, or standard operating procedures. DoD standard practices may be cited as solicitation requirements without need for a waiver by the Milestone Decision Authority.
  6. Test Method Standards - per MIL-STD-1916, DoD Preferred Methods for Acceptance of Product, the purpose of a test method standard is to encourage defense contractors and other commercial organizations supplying goods and services to the US Government to submit efficient and effective prevention-based process control procedures in place of prescribed sampling requirements. The goal is to support the movement away from an Acceptance Quality Limited (AQL) or sampling-based inspection detection strategy to implementation of an effective prevention-based strategy including a comprehensive quality system, or Continuous Process Improvement (CPI) system in partnership with Government customers.


Non-Government Standards (NGS)

Nationally and internationally recognized technical, professional, and industry associations and societies (or "non-Government standards bodies (NGSBs)") prepare standards, many having potential application or impact in the DoD. Applicable references include:

  • Section 12(d) of Public Law (PL) 104-113, National Technical Transfer and Advancement Act of 1995, requires federal agencies to use NGSs and participate in their development to meet agency needs and objectives, when it is consistent with the agency’s mission, priorities, and budget resources.
  • OMB Circular A-119, Federal Participation in the Development and Use of Voluntary Consensus Standards and in Conformity Assessment Activities, provides government-wide guidance for implementing the public law.
  • Standardization Directory (SD) 9, DoD Guidance on Participating in the Development and Use of Non-Government Standards, provides guidance information on DoD participation in the development and use of NGSs.
  • DoDM 4120.24, Defense Standardization Program Procedures, enclosure 9, paragraph 4 states that "DoD uses adopted and unadopted NGSs directly as acquisition documents, as references in other documents, or as design or reference guides. While NGSs that have not been adopted may be used, action to adopt these documents is encouraged. Use of an NGS in the DoD suggests it is technically adequate to meet the needs of the adopting activity, custodians, and review activities, and coordination of the NGS may not be necessary. Where only a small portion of an NGS is needed, it may be more efficient to directly copy the pertinent portion into the government document after permission is obtained."

Commercial Standards

The policy of the DoD is to utilize to the maximum degree possible those non-Government standards which satisfy the needs of the military. The policy has its roots in the advent of acquisition reform in the early 1990’s. The move toward commercial off-the-shelf (COTS) components gained momentum as a result of the 1994 Secretary of Defense (SECDEF) Memorandum, Specifications and Standards – A New Way of Doing Business (often referred to simply as the "Perry Memorandum". This memorandum encouraged, where practical, the use of commercial standards in lieu of military standards and specifications. As a result, hundreds of military standards were cancelled, and the use of performance-specifications to describe desired capabilities and outcomes was initiated.


The Program Manager (PM) must balance the decision to standardize against specific mission requirements, technology growth, and cost effectiveness. Under the DoD’s performance based acquisition policies, it is primarily the contractor’s responsibility to recommend the use of standard materials, parts, components, and other items needed to meet performance requirements and satisfy other program elements, such as parts management and logistics support. However, interoperability, compatibility, and integration are key standardization goals that must be satisfactorily addressed for all acquisitions. These goals shall be specified and validated during the requirements generation process and throughout the acquisition life cycle.

In addition, PMs, in coordination with their Product Support Managers (PSM), should establish a Data Management (DM) system within the Integrated Data Environment (IDE) that allows every activity involved with the program to cost-effectively create, store, access, manipulate, and exchange digital data. This includes, at a minimum, the needs of the system engineering process, Modeling and Simulation (M&S) activities, Test and Evaluation (T&E) strategy, Product Support Strategy (PSS) as captured in the Life Cycle Sustainment Plan (LCSP), and other periodic reporting requirements. The PM/PSM should use existing infrastructure as appropriate and the summary in the Acquisition Strategy should briefly include leveraged and/or planned new development of IDE capabilities.

Finally, for additional information, visit the Defense Standardization Program (DSP) website, the DSP Specifications and Standards website, and the Acquisition Streamlining and Standardization Information System (ASSIST) database, which identifies approved defense and federal standardization documents, adopted non-government standards (NGS), and U.S. ratified materiel International Standardization Agreements (ISAs).