🔥 NADCAP
NADCAP-Accredited Anodizing: Audited Special-Process Sources
Of every certification a buyer can ask an anodizing shop to hold, NADCAP is the one that actually audits the tank line itself. Where ISO 9001 and AS9100 evaluate the management system, NADCAP's Performance Review Institute sends a technical auditor to verify solution analysis, rectifier calibration, pyrometry, and seal testing against rigorous checklists, which is exactly why aerospace primes mandate it for flight-hardware anodizing. This page breaks down what those audit criteria require and how to read an accreditation so you know precisely what is and is not covered.
NADCAPAS9100ISO 9001
NADCAP accreditation for anodizing runs under the Chemical Processing task group. The foundational audit is AC7004, the quality-system baseline for chemical processors, which establishes the QMS context, often layered over the shop's AS9100 or ISO 9001. On top of it sits AC7108, the job audit checklist for chemical processing, which is where anodizing is technically scrutinized. AC7108 verifies that the operator runs to a written, customer-approved process; that solution analysis is performed at the required frequency and recorded; that rectifiers and timers are calibrated; and that coating thickness and seal quality are measured by acceptable methods.
Pyrometry deserves its own mention because temperature control is integral to seal quality and bath stability, and NADCAP's pyrometry requirements (the AMS 2750 lineage applied where heat treatment or controlled-temperature operations are involved) drive thermocouple calibration, system accuracy tests, and temperature-uniformity surveys on relevant equipment. For seal and dye operations, bath temperature directly affects coating outcome, so the auditor confirms instruments are calibrated and the operating windows are honored.
The audit is also deeply records-driven. An auditor will pull recent jobs and trace them: was the solution within control limits on the day it ran, was the rectifier within calibration, were thickness readings taken at the required points, and was the seal test passed by the specified method. Findings are written against the specific checklist line, the shop submits root-cause and corrective action, and accreditation is granted or maintained only after those are accepted. This closed-loop, line-of-sight rigor is what buyers are paying for.
Why NADCAP Sits a Tier Above ISO 9001 for This Process
ISO 9001 asks whether the shop has a controlled process and follows it. NADCAP asks whether the process is technically correct for the aerospace specification and proves it by auditing the actual tank-side practice. That difference is not academic for anodizing, where a coating that looks fine can still be under-sealed, under-thickness, or improperly applied in ways no receiving inspection will catch.
The practical consequence is that NADCAP is effectively mandatory for flight-hardware anodizing across the major primes (Boeing, Airbus, Lockheed, RTX, GE, Honeywell and their tiers), while ISO 9001 alone serves commercial and industrial finishing. NADCAP also tends to come bundled in expectation with AS9100 at the shop level, since the aerospace quality system and the audited special process together satisfy the typical flowdown.
Another distinction: NADCAP accreditation is granular by process and by spec. A shop is accredited for specific processes such as sulfuric anodize, chromic anodize, hardcoat, and the associated AMS specs it demonstrated during audit, not for anodizing in the abstract. This granularity is the single most misread aspect of NADCAP, and it is the reason a buyer must read the accreditation scope rather than trusting the NADCAP logo on a website.
Reading the eAuditNet Accreditation Scope Before You Buy
NADCAP accreditations are maintained in eAuditNet, PRI's online system, and the qualified suppliers are searchable through the QML (Qualified Manufacturers List) function. Before placing work, confirm the shop appears as currently accredited for Chemical Processing and, critically, that the specific anodizing process and spec you need are inside its scope. A shop accredited for sulfuric anodize per AMS 2470 is not automatically accredited for chromic anodize or for Type III hardcoat per AMS 2468.
Check the accreditation status and expiration as well. NADCAP audits run on a recurring cycle, and merit status can lengthen the interval for strong performers, but an expired or suspended accreditation is a hard stop for flight work. The accreditation entry shows the current status; do not rely on a certificate the shop emailed you that may predate a downgrade.
Finally, match the scope to your drawing line by line. If your print calls AMS 2469 sulfuric anodize Type II Class 2 with a specific seal, confirm that exact combination is covered. Where the shop's scope is silent on your spec, the safe assumption is that it is not accredited for it, and you should either find a shop that is or obtain explicit written confirmation and customer approval before proceeding. Reading the scope correctly here prevents the most expensive surprise in aerospace finishing: parts rejected at source inspection because they were processed outside accreditation.
Records and Traceability You Should Receive
Because NADCAP audits the records, a NADCAP anodizer is well-positioned to deliver a strong documentation package. Expect a certificate of conformance citing the AMS or MIL spec, type, class, and the validated process, plus measured coating thickness at defined locations and the seal-quality result by the specified method (dye stain per ASTM B136 or admittance per ASTM B457). For salt-spray requirements, expect an ASTM B117 result by reference, whether in-house or third-party.
The deeper value is traceability: the shop can tie your lot to the solution-analysis record, the rectifier and pyrometry calibration status, and the process run sheet for the day the parts were anodized. On aerospace work this chain is routinely required and routinely audited, so a NADCAP shop should be able to produce it on request rather than scrambling. If your part is also under AS9100 with a first-article requirement, the AS9102 package will reference the NADCAP-accredited process.
Build your expectations into the purchase order. Specify the documentation deliverables, the seal-test method, any sacrificial-coupon requirement for thickness or coating-weight verification, and the record-retention term. A NADCAP-accredited shop is accustomed to this level of demand, and the discipline that earns the accreditation is the same discipline that produces clean, retrievable records for your file.
Frequently Asked Questions
NADCAP audits the technical practice of the chemical-processing line itself, not just the paperwork. Under the foundational AC7004 quality baseline and the AC7108 job audit checklist, a PRI technical auditor verifies that the shop runs to a written, customer-approved process; that solution analysis is performed at the required frequency and recorded; that rectifiers, timers, and temperature instruments are calibrated; that pyrometry requirements in the AMS 2750 lineage are met where controlled-temperature operations apply; and that coating thickness and seal quality are measured by acceptable methods. The audit is records-driven: the auditor pulls recent jobs and traces whether the solution was within control limits, the rectifier was in calibration, thickness was measured at the required points, and the seal test passed by the specified method. Findings are written against specific checklist lines and require accepted corrective action before accreditation is granted or maintained. That closed-loop, line-of-sight rigor is exactly why primes require it for flight hardware.
ISO 9001 asks whether the shop has a controlled process and follows it; NADCAP asks whether the process is technically correct for the aerospace specification and proves it by auditing the actual tank-side practice. For anodizing this distinction is decisive, because a coating that looks acceptable can still be under-sealed, under-thickness, or improperly applied in ways no receiving inspection catches. As a result, NADCAP is effectively mandatory for flight-hardware anodizing across the major aerospace primes, while ISO 9001 alone is appropriate for commercial and industrial finishing. NADCAP also typically rides with AS9100 at the shop level, since the aerospace quality system plus the audited special process together satisfy the standard prime flowdown. One more critical difference: NADCAP accreditation is granular by process and spec, so a shop is accredited for specific processes such as sulfuric, chromic, or hardcoat anodize and the AMS specs it demonstrated, not for anodizing in general.
NADCAP accreditations are maintained in eAuditNet, PRI's online system, and qualified suppliers are searchable through the QML function. Before placing work, confirm the shop is currently accredited for Chemical Processing and, most importantly, that the specific anodizing process and spec on your drawing are inside its scope. Accreditation is granular, so a shop accredited for sulfuric anodize per AMS 2470 is not automatically accredited for chromic anodize or Type III hardcoat per AMS 2468. Check the current status and expiration in eAuditNet rather than relying on a certificate the shop emailed you, which may predate a suspension or downgrade; merit status can lengthen the audit interval for strong performers, but an expired or suspended accreditation is a hard stop for flight work. Match the scope to your print line by line, and where the scope is silent on your exact spec, assume it is not covered and seek written confirmation and customer approval before proceeding.
Because NADCAP audits the records, an accredited anodizer is well-positioned to deliver a complete package. Expect a certificate of conformance citing the AMS or MIL spec, type, class, and validated process, plus measured coating thickness at defined locations and the seal-quality result by the specified method, dye stain per ASTM B136 or admittance per ASTM B457. For salt-spray requirements, expect an ASTM B117 result by reference. The deeper value is traceability: the shop can tie your lot to the solution-analysis record, the rectifier and pyrometry calibration status, and the process run sheet for the day the parts ran, which aerospace work routinely requires and audits. If the part is also under AS9100 with a first-article requirement, the AS9102 package will reference the NADCAP-accredited process. Specify your documentation deliverables, seal-test method, any sacrificial-coupon requirement, and record-retention term in the purchase order; a NADCAP shop is accustomed to this level of demand.
Usually not, and over-buying it wastes money. NADCAP carries a real premium over commercial anodizing because of the audit-driven solution control, calibration, pyrometry, and documentation overhead, plus generally lower throughput on carefully controlled work and longer lead times, commonly two to four weeks versus the one-to-two-week commercial norm. That premium is justified for flight hardware where a corrosion or fatigue failure is unrecoverable and a prime mandates the accreditation. For architectural extrusion, automotive trim, consumer hardware, hydraulics, and most heavy-equipment components, an ISO 9001 anodizer with anodizing inside its registered scope delivers the appropriate quality at a far better price and lead time. The right move is to match the certification to the destination: if a prime or OEM flows down NADCAP, source it; if your own engineering owns the spec and the part is commercial, NADCAP is paying for audit rigor your application does not require.
Last updated: July 2026
Find NADCAP-Certified Finishing / Anodizing Suppliers
Search verified finishing / anodizing shops that hold NADCAP.
No logins. No email gates. Just results.