First Article Inspection & PPAP for Injection Moulding: A Buyer's Guide

Updated: 2026-10-22

A sample report answers what was checked on identified parts. A production qualification also asks whether the agreed process and controls are appropriate for repeat supply. Specify the evidence you need before ordering rather than relying on the labels FAI, ISIR or PPAP to carry an unstated scope.

What should an FAI or ISIR report contain?

Record the part number and released revision, tool and cavity, sample identifiers, exact resin grade and batch, trial or production reference, inspection date and responsible reviewer. Link each reported characteristic to a numbered drawing feature. Show nominal value, limits, actual result, units, method and disposition. Identify features not measured and explain why; a partial report must not be presented as full dimensional inspection.

Specify whether the order needs every drawing characteristic or selected critical features. Ask how free-state dimensions, fixture restraint, measurement force and material conditioning will be handled. The most elaborate measuring equipment is not automatically the right method: it must access the feature without changing the part or interpreting a different datum system.

How do FAI, ISIR and PPAP differ?

FAI and ISIR describe first-sample inspection/reporting arrangements whose detailed scope must be agreed. PPAP is a structured production-part approval process. It can involve design records, dimensional and material evidence, process flow, risk analysis, a control plan, measurement-system studies, initial process studies and a Part Submission Warrant. A dimensional report alone does not constitute a complete PPAP.

Use the customer's current PPAP request, applicable manual and customer-specific requirements to establish submission level, retained records, required run conditions and authorised approval. Submission level is not a universal product-risk rating. Medical, automotive and other regulated applications require their own applicable customer and product requirements; “PPAP Level 3” is not a substitute for those requirements or proof of certification.

What can a small sample prove?

It can show the measured results of those identified parts under the stated conditions. It cannot by itself establish stable long-run production or a defensible defect rate. Before requesting Cpk or Ppk, agree the characteristic, sampling sequence, cavity treatment, measurement system, statistical method and acceptance criterion.

Capability indices depend on assumptions, process behaviour and how variation is estimated. Do not translate one index into a promised number of defects or treat a familiar threshold as mandatory for every component. A process may be off-centre, unstable or measured poorly even when a short sample looks acceptable.

Why must cavity results remain separate?

Consider an invented diameter requirement of 10.00 ± 0.05 mm. Cavities 1, 2 and 4 read 10.01, 9.99 and 10.00 mm; cavity 3 reads 10.08 mm and fails. The four-reading mean is 10.02 mm and conceals the failing result. These readings illustrate reporting, not a sufficient sample size or capability study. Keep cavity identity and investigate causes before deciding whether tool or process changes are justified.

What should the buyer put in the RFQ?

• The current drawing and CAD revision, numbered characteristics, datums and functional priorities.
• Exact material requirements, conditioning and any required lot certificates or test evidence.
• Full or partial dimensional scope; sample quantity and identification by cavity.
• Measurement methods, customer forms and any capability or measurement-system studies.
• Cosmetic and assembly criteria, approval authority and treatment of deviations.
• Report language/format, retained samples, document retention and reapproval triggers.

Separate trial parts, measurement, fixtures, outside testing and corrections in the requested quotation. Their price and schedule depend on the actual scope; do not assume they are included in a tooling tier. An approved report should lead to a defined production control plan, including what happens after a material, tool, process or site change.

Templates, next steps and references

Use the sample-approval pack for a cavity report, issue log and explicit release decision. It is a project worksheet, not an official PPAP form. Connect it with the T1 sampling guide and your project enquiry.

AIAG: PPAP defines the production-approval purpose. Protolabs inspection options provides manufacturer examples of separately scoped reports. Their commercial terms do not establish Nordmould services or acceptance limits.