SAFETY DESIGN AND EVALUATION CRITERIA FOR NUCLEAR WEAPON SYSTEMS
|Publication Date:||13 March 2020|
Responsibility and Scope.
Air Force activities shall apply Department of Defense (DoD) and Air Force safety criteria to design, develop, evaluate, troubleshoot, certify, and maintain nuclear weapon systems. Weapon system designers should constantly seek to design systems that significantly exceed minimum safety standards. (T-1).
Design agencies (e.g. Lockheed Martin, Northrop Grumman, Boeing, etc.) implement safety criteria from the start of weapon system development by including them in appropriate formal source documents. These documents include, but are not limited to, the program management directive, Stockpile-to-Target Sequence (STS), military characteristics, weapon system specifications, interface control document, systems engineering plan, and test and evaluation master plan.
The DoD Nuclear Surety Standards form the basis for the safety design criteria for Air Force nuclear weapon systems. The Surety Standards state that:
There shall be positive measures to prevent nuclear weapons involved in accidents or incidents, or jettisoned weapons, from producing a nuclear yield (equivalent to four pounds of TNT). (T-0).
There shall be positive measures to prevent deliberate prearming, arming, launching or releasing of nuclear weapons, except upon execution of emergency war orders or when directed by competent authority. (T-0).
There shall be positive measures to prevent inadvertent prearming, arming, launching, or releasing of nuclear weapons in all normal and credible abnormal environments. (T-0).
There shall be positive measures to ensure adequate security of nuclear weapons, as governed by DoD Manual (DoDM) S-5210.41, Nuclear Weapon Security Manual. (T-0).
To comply with the DoD Nuclear Surety Standards, the Air Force has implemented a set of minimum design criteria for their nuclear weapon systems. Criteria contained in this manual is consistent with AFI 91-101 and the DoD Nuclear Surety Standards. These criteria do not invalidate the safety requirements in other DoD publications. Air Force nuclear safety design certification activities shall apply the most stringent requirements, as applicable, from all requirements that apply to a given nuclear surety issue (final applicability of requirements for a given certification action is documented in the signed Certification Requirements Plan in accordance with AFI 63-125, Nuclear Certification Program). (T-1). Since the design surety criteria in this manual are not design solutions and are not intended to restrict the designer in the methods and techniques used to meet operational design requirements, they are not allinclusive. Air Force nuclear weapon system designers may add feasible and reasonable safety features as needed while meeting operational requirements because the Air Force goal is to incorporate maximum nuclear surety, consistent with operational requirements, from weapon system development to dismantlement. Refer to AFI 63-125 for details on the nuclear certification procedures. AFI 91-101 provides details on what is required to be nuclear safety design certified, while this document provides the design criteria for those items requiring Nuclear Safety Design Certification.
Safety Design Certification only covers weapon system designs or modifications that have an impact to nuclear surety. This means that all of the designs (hand calculations, models, simulations, analysis) are evaluated according to the four DoD Surety Standards before any fabrication of components. Air Force Safety Center, Nuclear Weapons Branch (AFSEC/SEWN) does not have an obligation to validate that the components were fabricated and manufactured to the exact specifications agreed to in the design, only that the design of the weapon and weapon system does not exceed the limitations of the STS. Test equipment used to perform Operational Certification and identified as requiring Nuclear Safety Design Certification per AFI 91-101 shall comply with all applicable General, Electrical, Hazard Prevention, and Test Equipment requirements of this manual. (T-1).