NADCAP (the National Aerospace and Defense Contractors Accreditation Program) accredits specific special processes: heat treat, non-destructive testing, welding, chemical processing, coatings, materials testing, and a handful of others. It doesn't certify a company's overall quality system the way AS9100 does. If your shop performs one of these processes on aerospace or defense parts, a prime contractor will likely require NADCAP accreditation for that specific process as a flow-down condition of doing business, regardless of your AS9100 status. Nadcap requirements are process-specific, checklist-driven, and focused on whether your records can prove a given process was run within spec. That's the discipline that makes fast, accurate recalls possible when something goes wrong.

What NADCAP accredits

NADCAP is administered by PRI (Performance Review Institute), on behalf of a subscriber base of aerospace and defense primes (Boeing, Lockheed Martin, Raytheon, and others) who jointly fund and rely on the program instead of each auditing their supply chain separately. The accreditation applies to a specific process at a specific facility, not to the company as a whole. Common accreditation categories:

Special process category	Typical scope
Heat treating	Furnace pyrometry, atmosphere control, hardness/microstructure results
Non-destructive testing (NDT)	Penetrant, magnetic particle, radiographic, ultrasonic inspection
Welding	Procedure qualification, operator qualification, weld inspection
Chemical processing	Anodizing, plating, chemical conversion coating, passivation
Coatings	Thermal spray, dry film lubricant, other specialty coatings
Materials testing laboratories	Mechanical and chemical test methods on materials/parts
Nonconventional machining/EDM	Laser, EDM, chemical milling, electrochemical machining
Composites	Layup, cure, bonding processes
Sealants	Application and cure of aerospace sealants

A shop that does its own heat treat and NDT in-house needs NADCAP accreditation for both, separately. Accreditation in one process doesn't extend to another, and losing accreditation in one doesn't necessarily affect the others.

NADCAP vs. AS9100: different layers of the same supply chain

These get confused constantly because both show up on the same customer quality clause. The distinction:

AS9100 certifies your overall quality management system: document control, nonconformance handling, CAPA, design controls if applicable. It applies to the whole company. See AS9100 for small shops for what that audit checks.
NADCAP accredits a specific special process against process-specific requirements (often referencing standards like AMS2750 for pyrometry, or NAS410 for NDT personnel certification). It applies to the process, at the facility performing it.

You can be AS9100 certified without any NADCAP accreditation if you don't perform special processes in-house. Most job shops subcontract heat treat and plating to accredited suppliers instead of accrediting their own line. Conversely, a plating house might hold NADCAP for chemical processing without ever pursuing AS9100 certification for a broader quality system, if their customers only need the process accreditation.

What a NADCAP audit checks

NADCAP audits are run by PRI-qualified auditors against detailed, publicly available checklists specific to each process (available through PRI's eAuditNet system). At a high level, every audit checks:

Process specification compliance: are you running the process per the exact specification your customer requires (e.g., AMS-H-6875 for heat treating steel), not a generic version of the process.
Equipment qualification and calibration: furnace surveys and pyrometry per AMS2750, calibration records for test and measurement equipment.
Personnel certification: operators and inspectors certified to the applicable standard (NAS410 for NDT, for example), with records proving current certification.
Job audits: auditors trace specific, real production jobs through your records from start to finish, checking that every required record exists and matches.
Record retention and traceability: can you produce the complete process record for a specific lot, on demand, including raw material certs, in-process records, and final test results.
Nonconformance and corrective action history: how you've handled past process escapes and whether the corrective action addressed the root cause.

Job audits are where shops most often get tripped up: an auditor doesn't just check that you have a procedure. They pull an actual work order from the recent past and verify every record required by the checklist exists, in the file, correctly filled out, for that specific job.

Records a special process needs on file

The exact list varies by process and by the referenced spec, but for most special processes an auditor expects to find, per lot or per run:

Process specification and revision used, matched to the customer's engineering requirement
Equipment used, with current calibration/qualification status
Process parameters achieved (time, temperature, chemistry, pressure, whatever the process controls)
Operator/inspector identification and certification status at time of the work
Raw material or incoming part certifications tied to that specific lot
In-process and final inspection/test results against the specification's acceptance criteria
Nonconformance records for anything outside spec, with disposition

If any one of these is missing for a job the auditor selects, it's a finding, and repeated or serious findings put the accreditation itself at risk, which is a business continuity problem if that process is a meaningful share of your revenue.

Lot genealogy: the real payoff

Lot genealogy is the record of exactly which raw material lots, work orders, and process runs went into a given finished part or batch. It's what turns "a furnace run had an atmosphere excursion" into a bounded, fast recall instead of an open-ended one.

Say a heat treat furnace's atmosphere control drifted out of spec for a two-hour window, discovered during a routine pyrometry check. Without solid lot genealogy, you can only answer "which parts were in the furnace during that window, and where did they go" by manually cross-referencing furnace load sheets, work order logs, and shipping records. That takes days, often can't be answered with full confidence, and pushes shops toward over-broad, expensive recalls to be safe.

With proper genealogy, the same question resolves to a query: every part number, work order, and lot/serial number that was in that specific furnace load, cross-referenced against which of those units already shipped, to which customer, on which sales order. A genealogy record that supports this needs, at minimum:

Furnace/process run ID, linked to the specific load
Every work order and lot/serial number included in that load
The raw material lot(s) that fed each of those work orders
Shipment records linking finished lot/serial numbers to customer and ship date

That chain (raw material lot → work order → process run → finished lot → shipment) is the same genealogy backbone used for AS9102 first article records and for any downstream recall. See what is lot and serial traceability for how that chain is typically modeled, and FAI and AS9102 forms for how first article data ties into the same record set.

Where systems fail this

The most common failure mode is genealogy split across systems that don't talk to each other, not a missing procedure. Furnace logs live on paper or in the equipment's own software, work orders live in the ERP, and shipping records live in a third system. Reconstructing genealogy across three systems under the time pressure of a real containment event is slow and error-prone, exactly when speed and accuracy matter most.

How Carbon supports special-process traceability

Carbon keeps raw material lots, work orders, process/routing data, inspection results, and shipments on one Postgres data model, so genealogy isn't reconstructed after the fact; it's the same record used to run production. A containment query (which finished lots came from this raw material lot or this process run) is a query against live data, not a multi-system reconciliation project. Because every table is reachable over a REST API, a nonconformance on a special process can automatically flag every downstream work order and shipment tied to the affected lot. Carbon doesn't replace the NADCAP audit or the process-specific record-keeping your accreditation requires, but it removes the fragmentation that turns a bounded containment action into a company-wide scramble.

Frequently asked questions

Does my shop need NADCAP accreditation?

Only if you perform a special process in-house (heat treat, NDT, welding, plating, etc.) and your aerospace/defense customer's quality clause requires accreditation for that process. Most job shops instead subcontract special processes to already-accredited suppliers.

How is NADCAP different from ISO 17025 lab accreditation?

ISO 17025 accredits testing/calibration laboratory competence generally; NADCAP accredits specific aerospace special processes against aerospace-industry-specific requirements. Some materials testing labs hold both.

How often are NADCAP audits?

Accreditation cycles are risk-based, typically every 12 to 24 months depending on your audit history and PRI's risk assessment, plus supplemental audits if significant nonconformances or process changes occur.

What happens if a shop loses NADCAP accreditation?

Any customer requiring that specific accreditation can no longer accept parts processed under it, which functionally halts that revenue stream until accreditation is restored. This is why job-audit readiness has to be continuous, not a pre-audit scramble.

What is lot genealogy, in one sentence?

The complete, traceable chain linking raw material lots through every work order and process run to the finished part and its shipment, so a nonconformance found anywhere in the chain can be traced to exactly which finished units are affected.

Try Carbon on your traceability and genealogy data

If reconstructing lot genealogy across systems is slowing down your containment process, try Carbon free for 30 days and see raw material lots, work orders, and shipments running on one queryable data model. Prefer to inspect the traceability model first? The source is on GitHub.

NADCAP explained: special processes and lot genealogy