What is IPC-A-610
IPC-A-610 ("Acceptability of Electronic Assemblies") is the global visual inspection standard published by IPC. It defines what a "good" solder joint, component placement, cleanliness level, and damage state looks like — across three classes of end-product reliability:
| Class | Use case | Examples |
|---|---|---|
| Class 1 | Consumer | Toys, low-cost electronics |
| Class 2 | Industrial / commercial | Industrial controls, telecom, automotive non-safety |
| Class 3 | High-reliability | Medical (life-support), defense, aerospace, space |
Energetika-VDS ships IPC-A-610 Class 2 as default on every assembly order. Class 3 is available on request — see our quality and traceability page for the audit chain.
Key acceptance criteria differences
The standard runs 600+ pages. Here are the most common Class 2 vs Class 3 differences EMS inspectors apply day-to-day:
| Criterion | Class 2 | Class 3 |
|---|---|---|
| Plated through-hole fill | ≥75% | ≥75% (same — but vertical fill rules tighter on bottom) |
| Wetted solder height (chip) | ≥25% of side termination | ≥50% of side termination |
| Wetted solder height (gull-wing lead) | ≥50% of lead height | ≥50% (same) but heel fillet mandatory |
| Solder ball count | ≤5 per 600 mm², no contact | ≤3 per 600 mm², no contact, none within 0.13 mm of conductor |
| Exposed copper on PTH barrel | Acceptable | Not acceptable |
| Component tilt | ≤25° | ≤10° |
| Lifted lead | Allowed if joint OK | Not allowed |
| Voids in BGA | ≤25% area | ≤9% area (some specs say 4%) |
| Flux residue | Visual only | Cleanliness measured to J-STD-001 |
| Inspection coverage | Sample (AQL 1.0-2.5) | 100% inspection |
When Class 3 is mandatory
Class 3 is not a "premium" tier you choose for prestige — it is required when the product specification calls it out. Triggers:
- Medical class IIb and III devices (implantable, life-support) per IEC 60601 and ISO 13485
- Defense procurement under MIL-PRF-31032, J-STD-001ES (space addendum), or customer-specific PPAP
- Aerospace under AS9100 / EN 9100, especially for safety-critical avionics
- Space — IPC-J-STD-001 Class 3/A (space addendum) effectively replaces 610 here
- Industrial automation with safety integrity levels (SIL 2-3) — depends on the integrator
If your product is general industrial, telecom, consumer wearables, EV chargers (non-safety), automotive infotainment, or commercial IoT — Class 2 is the right choice.
The cost premium — where does the 8-20% go
| Cost driver | % of premium |
|---|---|
| Slower inspection (100% vs sample) | 35-45% |
| Certified operators (IPC-A-610 CIS/CIT) | 15-20% |
| Tighter rework loops | 15-20% |
| Documentation and traceability | 10-15% |
| Material upgrades (cleanliness, flux) | 10-15% |
On a €15/board, 1000-unit order, Class 3 adds €1200-3000 over Class 2. For a medical device that ships at €2000 each, that is rounding error. For a €40 industrial sensor, it would crater margin — so spec only what you need.
What Class 3 does NOT do
A common misconception: Class 3 means "better reliability." It does not. Class 3 means tighter visual workmanship acceptance at the EMS. Long-term field reliability is dominated by:
- Component derating (designer)
- Thermal management (designer)
- Conformal coating and enclosure (designer + EMS)
- BGA voiding control (process — see our BGA guide)
- DFM (design — see our DFM checklist)
Class 3 with a bad thermal design still fails. Class 2 with good design and component derating outlasts Class 3 every time. Choose Class 3 because the spec demands it, not because you think it makes the board more reliable.
How Class 3 is verified
At Energetika-VDS Class 3 orders run through:
- Operator certification — IPC-A-610 CIS (Certified IPC Specialist) on every operator touching the board
- 100% AOI inspection instead of sample-based — every board, every joint
- X-ray on every BGA and QFN — sourced through partners, on every board (Class 2 = sample)
- Cleanliness test — J-STD-001 ROSE or ion chromatography on every batch
- Documented serial-number traceability — operator, machine settings, reflow profile log per board
- First-article inspection report — signed before mass production begins
See our inspection and testing capabilities for the full equipment list.
Choosing the right class
| If your product is... | Choose |
|---|---|
| Consumer wearable, toy, gift item | Class 1 (we still default Class 2) |
| Industrial sensor, telecom, EV charger | Class 2 |
| EV battery management (safety-critical) | Class 2 with extra X-ray |
| Medical class IIa monitor | Class 2 with ISO 13485 docs |
| Medical class IIb/III implantable | Class 3 — mandatory |
| Military fire-control, avionics | Class 3 — mandatory |
| Satellite payload | Class 3 + J-STD-001ES |
Submit your RFQ with the class clearly specified. Class 3 changes our quote, lead time, and process — flag it upfront. Try the quote estimator to see the cost band before submitting.
Frequently asked questions
What is IPC-A-610? The global visual acceptance standard for electronic assemblies, published by IPC. It defines what a "good" solder joint, component placement, and finished assembly looks like across three reliability classes.
Class 2 vs Class 3 — what's the difference? Class 3 has tighter workmanship limits (no exposed copper on PTH, ≤10° tilt, lower void rates, no lifted leads), 100% inspection instead of sample-based, certified operators, and documented traceability. Class 2 is industrial/commercial; Class 3 is for life-support, defense, and aerospace.
Do I need Class 3? Only if your product specification, regulator, or customer contract calls for it. Medical class IIb/III, defense procurement, aerospace, and space applications require Class 3. Industrial, telecom, automotive non-safety, and consumer products run Class 2 — and gain nothing from Class 3 except cost.
How much more does Class 3 cost? Typically 8-20% on assembly labour over Class 2. On a €15/board 1000-unit order, that is €1200-3000. The premium pays for slower inspection, certified operators, tighter rework, and full documentation — not for better field reliability.