nasa-npr-7150

Classify each system or subsystem containing software at the highest applicable class (A-F) per SWE-020 and Appendix D, using five factors: usage within a NASA system, system criticality, human dependence, complexity, and Agency investment. Ambiguity always rounds up to the higher class.

The Requirements Mapping Matrix (Appendix C) maps every NPR requirement against a project by software class. An X cell means the requirement is mandatory for that class; the matrix also records Not-Applicable calls and approved tailoring with authority signatures.

SWE-219 mandates 100% MC/DC coverage for safety-critical components, and SWE-220 caps cyclomatic complexity at 15 with exceedances reviewed and waived with rationale. These gates reinforce the SWE-134 behavioral safe-state requirements.

The directive binds NASA Headquarters and Centers directly. It reaches JPL, contractors, grant recipients, and agreement parties only to the extent incorporated through a contract, grant, or agreement, and it is not retroactive.

It does not cover detailed software assurance and safety procedures (NASA-STD-8739.8), implementation how-to and record content (NASA-HDBK-2203), the systems engineering process framework (NPR 7123.1), or program and project management (NPR 7120.5).