Reference & AI

DAFMAN 91-119

Air Force

SAFETY DESIGN CRITERIA FOR NUCLEAR WEAPON SYSTEMS SOFTWARE

Reviewed by Guilherme Correia, active-duty U.S. Air Force

DAFMAN 91-119, "SAFETY DESIGN CRITERIA FOR NUCLEAR WEAPON SYSTEMS SOFTWARE", is a Department of the Air Force publication, dated March 11, 2020, certified current July 15, 2026.

Published

March 11, 2020

certified current July 15, 2026

OPR

AF/SE

Headquarters, Department of the Air Force

Official document

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DAFMAN 91-119 — index record

NumberDAFMAN 91-119
TitleSAFETY DESIGN CRITERIA FOR NUCLEAR WEAPON SYSTEMS SOFTWARE
PublishedMarch 11, 2020
Certified currentJuly 15, 2026
Guidance memorandumJuly 15, 2026
Office of primary responsibilityAF/SE
Issued byHeadquarters, Department of the Air Force
Status on the indexCurrent
Last index actionGM, July 15, 2026
Source indexAir Force e-Publishing
Index last readOctober 20, 2026

Copied from Air Force e-Publishing (index). The publication itself is the authority; this page does not summarize or interpret it. Verify the current edition on the index before acting.

From the publication itself

Text below is lifted mechanically from the official PDF (39 pages, read October 20, 2026) with no editing or interpretation. Quote the document, not this page.

Purpose, in the publication’s words

This manual implements Department of the Air Force Instruction (DAFI) 91-101, Air Force Nuclear Weapons Surety Program. It applies to all organizations that design, develop, modify, evaluate, operate or acquire Air Force nuclear weapon systems. This manual applies to all civilian employees and uniformed members of the Regular Air Force, Air Force Reserve, Air National Guard, and the United States Space Force (USSF) unless and until such time as separate service guidance is published by the USSF. Once the USSF has published its own guidance, and that guidance shall prevail in application to the USSF. Ensure that all records generated as a result of processes prescribed in this publication adhere to AFI 33-322, Records Management and Information Governance Program, and are disposed of in accordance with the Air Force Records Disposition Schedule, which is located in the Air Force Records Information Management System. Refer recommended changes and questions about this publication to the Office of Primary

Summary of changes, as printed

This interim change revises Air Force Manual (AFMAN) 91-119 by making changes for grammar and style, clarification of requirements, formatting, and conversion to a Department of the Air Force Manual (DAFMAN). Attachment 2 is a new section that defines the acceptable use of continuous delivery methodologies. This interim change incorporates exceptions to essential facility systems requirements, updates to the general software safety standards, clarification on the definition of Arm, clarification on the independence of the Development Organization and the Verification Organization and their independence responsibilities, additional applicability for Nuclear Safety Regression Testing, caveats for testing of built-in-test and test equipment software, addition of review process to development process requirement, addition of integrity checking and navigation validation requirements, and suggestions for interrupt disabling.

Contents

  1. Chapter 1—ROLES AND RESPONSIBILITIESp. 6
  2. Chapter 2—GENERAL STANDARDS AND CONTROLp. 7
  3. Chapter 3—CRITICAL SIGNALSp. 11
  4. Chapter 5—VERIFICATION GUIDELINESp. 26
  5. Chapter 7—SAFETY AND RELIABILITYp. 32
  6. Chapter 8—GENERAL SOFTWARE REQUIREMENTSp. 33
  7. Chapter 9—APPLICATION SOFTWARE REQUIREMENTSp. 47
  8. Chapter 10—PROGRAMMABLE LOGIC DEVICE REQUIREMENTSp. 52
  9. Attachment 1—GLOSSARY OF REFERENCES AND SUPPORTING INFORMATIONp. 54
All 71 contents entries
  1. Chapter 1—ROLES AND RESPONSIBILITIESp. 6
  2. 1.2. Program Managers through the System Program Office shall:p. 6
  3. 1.3. Development Organizations shall:p. 6
  4. 1.4. Verification Organizations shall:p. 6
  5. 1.5. AFSEC/SEWN shall:p. 6
  6. Chapter 2—GENERAL STANDARDS AND CONTROLp. 7
  7. 2.1. Philosophyp. 7
  8. 2.2. Applicabilityp. 7
  9. 2.3. DoD Nuclear Surety Standardsp. 8
  10. 2.4. National Security Agency (NSA) Certificationp. 8
  11. 2.5. Department of Energy (DOE) Certificationp. 9
  12. 2.6. Air Force Criteriap. 9
  13. 2.7. Deviationsp. 9
  14. Chapter 3—CRITICAL SIGNALSp. 11
  15. 3.1. Definitionp. 11
  16. 3.2. Impact on Critical Signalsp. 12
  17. 3.3. Software Effects on Critical Signalsp. 12
  18. 3.4. Critical Signal Analysisp. 13
  19. 4.1. Applicabilityp. 14
  20. 4.2. Nuclear Safety Objectives (NSO)p. 14
  21. 4.3. Nuclear Safety Requirements (NSR)p. 14
  22. 4.4. Verificationp. 14
  23. 4.5. NSATEp. 20
  24. 4.6. NSCCAp. 22
  25. 4.7. Nuclear Safety Regression Testingp. 25
  26. Chapter 5—VERIFICATION GUIDELINESp. 26
  27. 5.1. Verification Type Guidelinesp. 26
  28. 5.2. Safety Certificationp. 28
  29. 5.3. General Verification Guidelinesp. 29
  30. 6.1. Introductionp. 30
  31. 6.2. Transmission of Critical Software or Critical Datap. 30
  32. 6.3. Physical Mediap. 30
  33. 6.4. Write Once Read Many Mediap. 30
  34. Chapter 7—SAFETY AND RELIABILITYp. 32
  35. 7.1. Introductionp. 32
  36. 7.2. Reliabilityp. 32
  37. 7.3. Safetyp. 32
  38. Chapter 8—GENERAL SOFTWARE REQUIREMENTSp. 33
  39. 8.1. Applicabilityp. 33
  40. 8.2. Development Standardsp. 33
  41. 8.3. Certification Configurationsp. 35
  42. 8.4. Self-Modifying Codep. 36
  43. 8.5. Program Loading and Initializationp. 36
  44. 8.6. Memory Protectionp. 37
  45. 8.7. DELETEDp. 37
  46. 8.8. Memory Wear Protectionp. 37
  47. 8.9. Safe Initialization and Shutdownp. 37
  48. 8.10. Fault Detection and Fault Responsep. 38
  49. 8.11. Human Intentp. 39
  50. 8.12. Internal Data Formats and Verificationp. 41
  51. 8.13. External Data Formats and Verificationp. 42
  52. 8.14. Securityp. 43
  53. 8.15. Coding Prohibitions and Analysisp. 43
  54. 8.16. Real-Time Processingp. 44
  55. 8.17. Aircraft-Unique Requirementsp. 45
  56. 8.18. Multifunction Control and Displaysp. 45
  57. 8.19. Essential Facility System Requirementsp. 46
  58. Chapter 9—APPLICATION SOFTWARE REQUIREMENTSp. 47
  59. 9.1. Applicabilityp. 47
  60. 9.2. Programming Languagesp. 47
  61. 9.3. Memory Characteristics of Application Softwarep. 48
  62. 9.4. Real-Time Embedded Systemsp. 48
  63. 9.5. Real-Time Operating Systems (RTOS) and Run-Time Systemsp. 49
  64. 9.6. General-Purpose Computer Systemsp. 50
  65. Chapter 10—PROGRAMMABLE LOGIC DEVICE REQUIREMENTSp. 52
  66. 10.1. Applicabilityp. 52
  67. 10.2. Hardware Description Languagesp. 52
  68. 10.3. Memory Characteristics of Programmable Logic Devicesp. 52
  69. 10.4. Programmable Logic Device Verificationp. 53
  70. 10.5. Application Specific Integrated Circuit Verificationp. 53
  71. Attachment 1—GLOSSARY OF REFERENCES AND SUPPORTING INFORMATIONp. 54

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Air Force index

REF: DAFMAN 91-119, effective March 11, 2020

Air Force e-Publishing — DAFMAN 91-119

This is an index record, not the publication. The official PDF is the authority; verify the current edition before acting.

Reviewed by Guilherme Correia · Military Toolkit editorial

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