walls or protrusions are the 
equivalent of ≥2 trace, (e.g., melt pool, bead, 
scan path) widths in cross section? 
 X  0 2  
Critical regions of the part do not require 
support structure? X X X 0 2  
1 In the context of the assessment of AM risk, the adequacy of a proof test is determined by the degree to which the test 
meets its assigned objectives. For a workmanship proof test, at any given location in the part the proof test is considered 
adequate when the state of stress in the part during the proof test exceeds the state of stress in the part during operation by 
the required proof factor. If the proof test conditions do not fully replicate the operational environment, as is typically the 
case, the proof and operational stresses are compared using directional stress components with any needed corrections for 
environment. For the rare case of quantitative flaw screening by proof test as an anchor to fracture control requirements, 
the adequacy of the proof test is determined only by the ability of the applied proof test stress conditions to screen the 
critical initial flaw size for operation by causing failure, leak, or other clearly detectible damage to the part during the 
proof test. Just as in the workmanship proof test, the adequacy of a proof test for quantitative flaw screening is likely to 
vary throughout the part. Demonstrating the adequacy of a quantitative proof test is non-trivial and must be coordinated 
intently with the structures and fracture control communities. 
2 Fatigue-critical surfaces are locations where fatigue analysis and surface condition assumptions influence the outcome of 
the structural assessment. 

4.4 Quality Assurance 

 Quality Management Systems 

[AMR-13]  A QMS compliant to SAE AS9100, Quality Management Systems – Requirements 
for Aviation, Space, and Defense Organizations, or an alternate QMS approved by the CEO and 
NASA, documented or referenced in the AMCP, shall be in place for all entities involved in the 
design, production, and post-processing of AM hardware. 

[Rationale:  A QMS is required to ensure necessary process controls and mitigate risks 
associated with noncompliance. The AS9100 QMS requirement applies because an AM process 
is considered “complex” per NPD 8730.5, NASA Quality Assurance Program Policy, due to 


significant reliance on process controls for the reliability of the product. AM parts in Class A are 
also considered “critical” per NPD 8730.5. 

Note:  Alternate QMS standards or supplier accreditation systems are more likely to be relevant 
at the subtier supplier levels (e.g., raw materials, post-processing, etc.) and should be 
considered by the CEO and NASA whenever reasonable. 

Nadcap™ accreditation for L-PBF is recommended but not required. 

 Quality Records 

NASA will evaluate the supplier’s adherence to AS9100 configuration management requirements 
by confirming that formal configuration management processes and systems are used to control 
the following work products, documents, data, and records, as a minimum: 

1. Process documents and specifications. 
2. Part drawings. 
3. Test reports (related to QMPs, witness tests, etc.). 
4. Shop travelers. 
5. Build files. 
6. Build records. 
7. Inspection results. 
8. Nonconformance and corrective action records. 
9. Records supporting the supplier’s certification of product conformance. 

Requirements and processes for assurance of QMSs can be found in NPR 8735.2, Management 
of Government Quality Assurance Functions for NASA Contracts, and AS9100. Per these 
documents, projects are required to use a quality assurance surveillance plan that includes a 
focus on a supplier’s QMS. 

4.5 Equipment and Facility Control Plan (EFCP) 

[AMR-14] All equipment integral to the AM process, and facility-specific processes and 
procedures, shall be under the control of a CEO-approved EFCP developed in accordance with 
NASA-STD-6033, Additive Manufacturing Requirements for Equipment and Facility Control, 
prior to the production of flight hardware. 

[Rationale:  Proper qualification, calibration, and maintenance of AM equipment and its 
associated equipment are essential to production of reliable AM parts.] 

The AM part producer is expected to develop and maintain the EFCP, which is to be approved 
by the CEO. The requirement for the EFCP may be met by leveraging existing documentation for 
control of equipment and facilities if all requirements of this section are addressed, all 


documents are configuration controlled in the QMS, and the documents that make up the EFCP 
are identified in the AMCP per section 4.5 of this NASA Technical Standard. 

4.6 Fracture Control 

[AMR-15]  All AM parts used in hardware subject to fracture control shall be classified and 
assessed to NASA-STD-5019 with the following limitations: 

a. AM parts are not to be categorized as non-fracture critical low-risk parts, per NASA-
STD-5019. 

b. AM parts are not to be categorized as fracture critical lines, fittings, and other 
pressurized components, per NASA-STD-5019, section 7.2.4, and instead are to follow the 
general approach for assessing fracture critical metallic parts per NASA-STD-5019, section 7.3. 

[Rationale:  For hardware with NASA-STD-5019 imposed, AM parts, like all others, are subject 
to the fracture control process. The “low risk” and “pressurized lines, fittings, and components” 
categories assume the use of materials with low risk of having defects introduced during all 
manufacturing processes, which permits reduced inspection and assessment requirements. As 
currently defined in NASA-STD-5019, sections 6.2.5 and 7.2.4(a), these categories are 
considered insufficient to manage the process control risks inherent to AM parts.]  

Note that sub-part (b) of this requirement does not prohibit the use of AM for fracture critical 
pressurized lines, fittings, and other components. Instead, it prohibits the use of NASA-STD-
5019, section 7.2.4(a), as the sole means of fracture control for fracture critical pressurized AM 
parts and invokes the full content of NASA-STD-5019, section 7.3, for this purpose. It is assumed 
that the design burst, proof pressure, leak test, and other applicable requirements in AIAA S-080, 
Space Systems - Metallic Pressure Vessels, Pressurized Structures, and Pressure Components, 
are met for any fracture critical pressurized AM parts. 

This NASA Technical Standard relies upon the latitude granted to the responsible fracture 
control board (RFCB) by NASA-STD-5019 to determine the adequacy of the overall fracture 
control rationale for AM hardware. It is expected that fracture control will frequently be 
implemented through an RFCB-approved alternative approach (see NASA-STD-5019) that uses 
a combination of process control, inspections, proof and other acceptance tests, analysis, and/or 
damage tolerance testing.  


4.7 Unplanned Interruptions 

[AMR-16]  Any unplanned build interruption, including planned interruptions occurring outside 
approved limits, shall be documented as a nonconformance and traceable via a records 
management system controlled by the QMS. 

[Rationale:  Unplanned interruptions in the AM process are a sign of a deviation in the steady-
state process, often resulting from an imperfection in the build or a fault in the machine. 
Treating an unplanned interruption as a nonconformance ensures the quality risk is 
characterized and mitigated.]  

Every effort should be made to eliminate build interruptions. 

Unplanned build interruptions may be restarted only if a nonconformance is documented and 
qualified restart procedures exist and are followed. The QMP defines the limitations for a 
planned interruption and qualifies the procedures for handling the interruption and restoration 
of the build process. 

4.8 Nondestructive Evaluation (NDE)  

 Class A Parts 

 Quantitative NDE 

[AMR-17]  All Class A parts shall receive quantitative NDE with full coverage of the surface 
and volume of the part, including verifiable detection of critical initial flaw size in fracture 
critical damage tolerant parts, with any coverage limitations due to NDE technique(s) and/or part 
geometry documented in the PPP per section 7.3 of this NASA Technical Standard.  

[Rationale:  NDE provides a necessary degree of quality assurance for AM parts in addition to 
the process controls of this NASA Technical Standard. No methodology currently exists to 
preclude all AM process failure modes through the available manufacturing process controls.] 


 NASA-STD-5009 Special NDE Approach 

[AMR-18]  The NDE approach for Class A parts shall meet the Special NDE requirements of 
NASA-STD-5009, Nondestructive Evaluation Requirements for Fracture Critical Metallic 
Components, and be documented in the PPP. 

[Rationale:  The defects of interest in AM are of a different nature than those listed in Tables 1 
and 2 of NASA-STD-5009, and AM microstructures can impact the effectiveness of NDE 
methods. Therefore, all inspections of fracture critical AM hardware should be treated as 
Special NDE.] 

The minimum detectable flaw sizes (see Table 1 of NASA-STD-5009) may be used as a guide but 
must be demonstrated prior to use as acceptance criteria. All method-specific requirements 
listed in the Standard NDE section should be used as guidance for traditional NDE methods. 

AM processes offer a unique opportunity to build hardware for demonstration of defect detection 
directly in the part. A demonstration part with simulated defects, surface connected and 
volumetric, can be built with modest development investment.  

Alternative flaw screening methods for Class A parts (e.g., proof testing) may be feasible with 
full justification provided in the PPP.  

 Class B Parts 

 Process Control NDE 

[AMR-19]  All Class B parts shall receive NDE for process control with full coverage of the 
surface and volume of the part, with any coverage limitations due to NDE technique(s) and/or 
part geometry documented in the PPP. 

[Rationale:  NDE for process control requires the use of physical reference standards for 
calibration and acceptance criteria based on the capability of the NDE technique but does not 
require quantitative validation of flaw detection.] 

Targeted approaches for NDE can be proposed and approved per the PPP. 


 NASA-STD-5009 NDE Approach 

[AMR-20]  The NDE approach for Class B parts shall meet the requirements of NASA-STD-
5009 and be documented in the PPP. 

[Rationale:  The requirements in NASA-STD-5009 establish important controls, including the 
definition, validation, documentation, and approval of all NDE procedures, standards, methods, 
and acceptance criteria; certification of NDE inspectors; NDE capability requirements; 
detection and reporting requirements; disposition of flaws; documentation control; and records 
retention.] 

Alternative post-build quality assurance methods for Class B parts (e.g., proof testing), as well 
as a reduction in NDE scope for Class B parts, may be feasible with full justification provided in 
the PPP.  

Accommodations for Class B inspections may be appropriate (e.g., using a radiographic 
inspection sensitivity level of 2-2T). 

Standards with NDE acceptance criteria for welding or casting quality are not generally 
considered applicable to AM parts but may be used for guidance. 

A full-height contingency witness specimen as described in Table 5 of this NASA Technical 
Standard can be inspected to investigate abnormal build conditions that may have occurred. 

For additional commentary on NDE methods and techniques for metal AM spaceflight 
hardware, see MSFC-STD-3716, Standard for Additively Manufactured Spaceflight Hardware 
by Laser Powder Bed Fusion in Metals, Appendix B, section 6.2.14.2, and ASTM E3166, 
Standard Guide for Nondestructive Examination of Metal Additively Manufactured Aerospace 
Parts After Build.  

Nonconformance findings related to NDE are controlled by the QMS similar to other scenarios; 
for Class A parts, NDE indications of cracks, crack-like defects, volumetric defects, or other 
findings of undetermined source should be elevated to senior review and disposition as required 
by the applicable fracture control policy (e.g., a RFCB). 

Each project and CEO will have defined rules for resolution of nonconformance items, including 
which items are elevated for higher level review and risk visibility. Senior review of crack-like 
defects is important not only for the integrity of the nonconforming part, but also for 
understanding the process escape that created the condition. The common forum for senior 
nonconformance review in the NASA system is the Material Review Board (MRB). For fracture 
critical AM parts, the RFCB should be made aware of nonconformances in flight hardware 
involving defects. 


4.9 In-situ Process Monitoring 

[AMR-21]  Prior to use as a quantitative indicator of part quality for part acceptance, passive in-
situ process monitoring technologies shall be qualified by the CEO to the satisfaction of NASA 
in a manner analogous to other NDE techniques. 

[Rationale:  All processes that are used to establish quantifiable quality assurance metrics are 
qualified against established criteria to verify detection reliability, calibration, and 
implementation. If in-situ monitoring techniques are employed for such purposes, the need for 
such qualification is unchanged.] 

Certification of a passive in-situ process monitoring technology relies on a thorough 
understanding of the physical basis for the measured phenomena, a proven causal correlation of 
the measured phenomena to a defined defective process state, and a proven level of reliability for 
detection of the defective process state. 

If qualified in the manner stated above, an in-situ process monitoring technique can be used to 
complement NDE in the Integrated Structural Integrity Rationale of the PPP. At this time, even a 
qualified in-situ process monitoring method cannot be considered a complete replacement for 
NDE. 

Even if qualification is not desired, the use of in-situ process monitoring is encouraged as a 
source of process control data. This data can also be used to help guide targeted inspection. 

As discussed in section 1.4.2 of this NASA Technical Standard, closed-loop process control 
based on adaptive in-situ monitoring technologies that alter the defined AM process in response 
to monitored phenomena are not currently applicable technology per this NASA Technical 
Standard and cannot be used without prior approved tailoring. See further discussion on the 
concerns with qualification of closed-loop controls in section 1.4.2 of this NASA Technical 
Standard.  


4.10 Repair and Rework 

[AMR-22]  Explicit provisions controlling any operation used to repair or rework an AM part 
due to a defect (e.g., short feeds/fractures, cracks) or nonconformance (e.g., warping) shall be 
documented and implemented as follows for Class A and B parts: 

a. Repair operations require prior written authorization from the contract authority, as 
described in the AMCP. 

b. All repair operations require full documentation as a nonconformance record and are 
included in the production engineering record of the part.  

c. Unplanned part operations not part of the QPP that constitute a repair or rework 
include, but are not limited to, bending, blending, sanding, peening, grinding, machining, 
welding, or brazing for the purposes of defect removal and/or part restoration to drawing 
allowances. 

d. All repair operations require validation on material manufactured using the same 
QMP. 

[Rationale:  Uncontrolled or undocumented repair is not allowed for two reasons:  first, such 
repairs are a danger to the integrity of the part; and second, such repairs obfuscate process 
escapes and hinder the development and implementation of corrective actions.] 

See section 3.2 of this NASA Technical Standard for definitions of rework and repair. 

See section 8 in this NASA Technical Standard for additional information regarding the QPP. 

4.11 Witness Testing for Statistical Process Control 

Use of witness specimens provides evidence of process control throughout the build cycle. This 
concept is based on the assumption that process development is complete and that a fixed 
"steady state" process has been reached. The implementation of witness sampling will vary from 
part to part depending on part class, the build layout, and specific part requirements. The PPP is 
used to document the approach to witness specimen testing.  

The test direction of witness specimens is almost always in the Z-direction defined by the build 
height since the properties in that direction are typically most sensitive to degradation in the 
build process. Testing should be performed during process development to determine the 
appropriate test direction or directions for a particular AM process, machine, or material. 

The direction, diameter, length, and shape of the witness specimens should be the same as the 
QMP specimens. Geometric differences in specimens can cause differences in the measured 
strength and ductility, which can prevent statistical combination or comparison of qualification 


and production witness data. All samples should have consistent surface finish between witness 
and QMP specimens; with the exception of surface-finish-dependent-testing (e.g., fatigue 
testing), it is recommended that all samples be fully machined. The locations of the witness 
specimens in the build volume or on the build plate should be specified and kept consistent for 
all builds.  

Because acceptable witness specimen test results are a prerequisite to part acceptance, 
significant programmatic risks occur when witness specimen testing lags continued part 
processing and additional part production. Witness specimen test results should be generated as 
soon as possible to reveal potential systemic changes to the AM process so rapid intervention 
can reduce the impact to production. 

Witness specimens are used to identify systemic changes in process control. By their nature, 
build witness specimens represent a small sample of the spatial (location in build volume) and 
time aspects of the build; they cannot necessarily indicate local, transient, or intermittent loss of 
process control during a build. 

This NASA Technical Standard requires SPC to monitor the results of witness specimen testing. 
Witness specimens are intended to provide