A Word form that takes one engineering change from description to verified implementation: what changes and why, every affected drawing, program and document, the impact review, what happens to existing stock and WIP, when the change takes effect, and who approved it.
Manufacturing and design engineers who raise changes, the document controller who issues the new revisions, and the quality, production and purchasing leads who sign off on impact.
Whenever an approved change alters a drawing, specification, bill of materials, process, program or inspection method. Small shops often use one ECN form for request, approval and notice; larger ones raise an ECR first and issue the ECN once it is approved.
Tip: Search the master document list by part number before filling the affected-items table. A missed work instruction or inspection plan is the usual reason an old revision keeps running.
Header
ECN number, date, originator, part number and name, and change classification
Change description
Current condition, new condition and reason for change
Affected items
Every drawing, program, document, gauge and BOM with current and new revision
Impact review
Fit, form, function, cost, validation and customer-notification assessment by function
Disposition and effectivity
Stock, WIP and open-order disposition, and the point where the change takes effect
Approvals and verification
Sign-off by function and evidence the change was implemented
Example ECN for Example Precision Co., a fictional machine shop, enlarging a clearance hole on a bracket. Part numbers, quantities and costs are invented for illustration.
| ECN number | ECN-2026-041 |
|---|---|
| Part | 10-2240 Mounting bracket |
| Classification | Minor: affects fit, not form or function at the customer interface |
| Current condition | Hole A Ø6.60 ±0.10 mm (Rev C) |
| New condition | Hole A Ø6.80 ±0.10 mm (Rev D) |
| Reason | Coated M6 fasteners bind in the Rev C hole at assembly |
| Item | Current rev | New rev | Owner |
|---|---|---|---|
| Drawing 10-2240 | C | D | Design Engineer |
| CNC program O2240 | 3 | 4 | Programmer |
| Work instruction WI-2240 | B | C | Manufacturing Engineer |
| Inspection plan IP-2240 | B | C | Quality Engineer |
| Pin gauge Ø6.70 / Ø6.90 go/no-go | New | GA-118 | Quality Engineer |
| Stock | Quantity | Disposition |
|---|---|---|
| Finished Rev C in stores | 120 | Rework: re-drill Hole A to Ø6.80 and re-inspect |
| WIP before drilling | 40 | Complete to Rev D |
| Open purchase orders | 0 | None affected |
| Effectivity | — | Work order WO-5512 onward, 2026-08-03 |
| Field | What to enter | Example |
|---|---|---|
| ECN number | Unique, sequential and never reused. Reference it in the revision block of every affected document. | ECN-2026-041 |
| Classification | Your own categories, such as major/minor, based on whether fit, form or function at the customer is affected. Major changes usually need customer approval. | Minor |
| Current / new condition | Quote the actual dimension, material or step before and after. Avoid "updated per markup". | Ø6.60 ±0.10 → Ø6.80 ±0.10 |
| Reason | The problem or request that triggered the change, with a reference (NCR, customer request, cost reduction). | Fasteners bind at assembly (NCR-0187) |
| Affected items | Every controlled item that references the part, each with current and new revision and an owner. | WI-2240 B → C |
| Impact review | Each function records yes or no for impact on fit, form, function, cost, tooling, validation and customer notification, with a comment. | Quality: new gauge needed |
| Disposition | Use as is, rework, scrap or return for stock, WIP and open orders, with quantities. | 120 rework, 40 complete to Rev D |
| Effectivity | A date, serial number, lot or work order from which only the new revision is used. | WO-5512 onward |
| Implementation verified | Who confirmed the new revisions are at the point of use and old copies removed, and when. | Quality Engineer, 2026-08-04 |
Usage varies by company. Commonly, an engineering change request (ECR) proposes a change, an engineering change order (ECO) authorizes it, and an engineering change notice (ECN) communicates the approved change to everyone affected. Many small shops combine all three in one form like this one.
Define it in your procedure. Many companies exempt purely editorial corrections that change no requirement, but anything affecting a dimension, material, process or inspection should go through an ECN.
At minimum the owner of the design or process and quality. Add production, purchasing and the customer when the impact review shows they are affected.
When the customer contract or standard requires it. In automotive this often means a PPAP resubmission; check your customer-specific requirements before release.
Keep them as long as the part is supported, plus your record-retention period. They are the history that explains each revision.
COPLAIN AI PLATFORM
Once an ECN is approved, describe the change to Coplain’s Document Update Assistant and it places the edit in each affected procedure and returns a redlined Word file for review.
Generate yours automatically with Coplain →