IPC-9202 Standard – SIR Test Protocol Using IPC-B-52 Test Assembly

If you need to qualify your manufacturing process for electrochemical reliability, IPC-9202 is the standard you’ll be working with. This test protocol defines exactly how to use the IPC-B-52 test assembly to generate objective evidence that your materials and processes won’t cause field failures from flux residues, ionic contamination, or electrochemical migration.

I’ve seen too many engineers struggle with process qualification because they didn’t fully understand what IPC-9202 requires. This guide covers everything you need to know—from test conditions and sample sizes to acceptance criteria and common pitfalls.

What is IPC-9202?

IPC-9202 is the “Material and Process Characterization/Qualification Test Protocol for Assessing Electrochemical Performance Using the IPC-B-52 Test Assembly.” The current version is Revision A, released in October 2022.

In practical terms, IPC-9202 tells you how to run Surface Insulation Resistance (SIR) testing on representative test assemblies to verify that your soldering process, cleaning procedures, and material choices won’t cause reliability problems in the field. It records changes in SIR over time under controlled temperature and humidity conditions.

The standard is specifically designed for the IPC-B-52 test vehicle, which represents a major step forward from older test coupons like the IPC-B-24. Unlike bare board coupons, the B-52 includes actual components that create entrapment sites for flux residues—just like your real products.

IPC-9202 Document Overview

When Do You Need IPC-9202 Testing?

IPC-9202 testing becomes necessary whenever you need to demonstrate process compatibility. The most common scenarios include:

Process Qualification: When you need to show that your manufacturing process meets the electrochemical requirements of J-STD-001 or similar specifications. This generates the “objective evidence” that auditors and customers ask for.

Process Changes: Any change to your assembly line that could affect cleanliness—new flux supplier, different cleaning chemistry, modified reflow profile, new board fabricator—should trigger requalification.

New Material Sets: When evaluating new solder pastes, fluxes, conformal coatings, or solder mask materials, IPC-9202 testing reveals compatibility issues before they become field failures.

Process Characterization: Even without formal qualification requirements, SIR testing helps optimize your process by comparing different parameter settings or material combinations.

Understanding the IPC-B-52 Test Assembly

The IPC-B-52 is specifically designed to represent real-world manufacturing conditions. Previous test vehicles like the IPC-B-24 were simple bare board coupons that didn’t reflect how flux residues actually behave under components.

IPC-B-52 Design Features

The IPC-B-52 test vehicle includes four separate areas:

The main SIR board includes both surface mount and through-hole technologies. Components are populated on both sides, meaning the test vehicle experiences two-pass reflow—exactly like most production boards.

Key Component Types on IPC-B-52

The dummy components used on IPC-B-52 have open internal connections—there’s no die inside. This is critical because it allows SIR testing to measure only the surface effects without interference from internal package resistance.

IPC-9202 Test Conditions and Parameters

IPC-9202 specifies environmental conditions designed to accelerate electrochemical failure mechanisms while remaining representative of real-world stress.

Standard SIR Test Conditions per IPC-9202

The 40°C/90% RH condition is the most commonly used for process qualification. The elevated temperature and humidity create an electrolyte layer on the board surface that accelerates ionic migration and dendrite growth—the same mechanisms that cause field failures in humid environments.

Some materials perform better at 40°C/90% RH while others show better behavior at 85°C/85% RH. If your end application involves high-temperature operation, testing at both conditions may be warranted.

Measurement Frequency

SIR measurements should be taken continuously or at regular intervals throughout the test duration. Most modern AutoSIR systems record data every few minutes, but at minimum you need:

• Initial reading (ambient, before exposure)
• Readings at 1, 4, 8, 24, 48, 96, and 168 hours
• Final reading at test completion

The first 24 hours often shows a resistance drop as the board acclimates to the humid environment. This is expected behavior—what matters is whether resistance stabilizes above the acceptance threshold.

Sample Sizes for IPC-9202 Testing

IPC-9202 distinguishes between process characterization and formal process qualification. The required sample sizes differ:

IPC-9202 Sample Size Requirements

Always include unprocessed control boards in your test lot. These “as-received” assemblies verify that the bare PCB itself doesn’t have contamination issues before you even apply your process. If the controls fail, investigating further processing is pointless until you resolve the incoming board quality issue.

IPC-9202 Acceptance Criteria

The primary acceptance criterion for IPC-9202 is maintaining SIR above the specified threshold throughout the test duration.

Pass/Fail Criteria

A single pattern dropping below 10⁸ Ω after the 24-hour grace period typically constitutes a failure. However, IPC-9202 recognizes that the appropriate threshold depends on your specific application. Consumer electronics might accept different limits than medical devices or aerospace hardware.

Post-Test Visual Examination

After SIR testing completes, every test pattern must be visually inspected under magnification. You’re looking for:

• Dendrite formation between conductors
• Discoloration of solder mask or metallization
• White residue deposits
• Conductor spacing changes
• Corrosion products

Document everything photographically. Even if SIR values remained acceptable, visible dendrite growth indicates marginal performance that might fail under slightly different conditions.

IPC-9202 vs. IPC-9201 vs. IPC-9203

These three standards work together but serve different purposes:

Comparison of IPC 92xx Standards

If you’re new to SIR testing, start with IPC-9201 to understand the underlying science. When you’re ready to implement testing, IPC-9202 provides the protocol, and IPC-9203 clarifies what you “should” versus “must” do.

Read more IPC Standards:

IPC Standards Explained: A Comprehensive Guide to PCB & Electronics Assembly Standards

IPC 2615 Standard Explained: PCB Dimensioning & Tolerancing Requirements

MIL-STD-2000A: Military Soldering Standards for Electronic Assemblies

MIL-STD-1686: ESD Control Program Requirements for Military Electronics

IPC 1791 Standard: Everything You Need to Know About Trusted PCB Certification

MIL-STD-883: Complete Guide to Microelectronics Test Methods

J-STD-048 Explained: Complete Guide to Product Discontinuance Notifications

MIL-STD-750: Semiconductor Device Test Methods Explained

MIL-STD-454: General Requirements for Military Electronic Equipment

IPC 9194: Complete Guide to SPC for PCB Assembly Manufacturing

MIL-STD-202: Electronic Component Testing Methods & Procedures

IPC 4110: Complete Guide to Cellulose Paper Specs for Printed Circuit Boards

Boundary Scan Testing (JTAG) in PCB Design: A Complete DFT Guide

Axiomtek IPC-950 Review: Specs, Features & Performance [2026 Guide]

MIL-PRF-55681: Military Ceramic Chip Capacitor Specification Guide

Implementing IPC-9202 in Your Facility

Here’s the practical workflow for running IPC-9202 process qualification:

Step 1: Obtain Test Materials

Order IPC-B-52 test boards from your same PCB supplier using identical materials and processes as your production boards. This is critical—using generic test boards from a kit defeats the purpose of representative testing.

Procure the dummy component kit separately. Suppliers like Practical Components and Topline offer complete B-52 CRET kits with all necessary components.

Step 2: Process Test Assemblies

Run the IPC-B-52 assemblies through your production line using the exact same equipment, materials, and process parameters. If you’re qualifying a reflow-only process, only populate the SMT patterns. For wave solder qualification, process the through-hole connectors.

Document everything: lot numbers for flux and solder paste, reflow profile data, cleaning parameters.

Step 3: Pre-Test Verification

Before investing in 168 hours of chamber time, check for solder shorts using a continuity tester. Any shorted patterns must be reworked or excluded from testing with documented justification.

Step 4: Run SIR Testing

Place test assemblies in the environmental chamber with proper spacing for air circulation. Connect bias voltage and begin data acquisition. Monitor for the full 168-hour duration (or longer for extended qualification).

Step 5: Post-Test Analysis

After the chamber run, perform visual inspection under 10-50x magnification. Document all observations. Compile SIR data into the required report format per IPC-9202 Section 7.

Common IPC-9202 Testing Pitfalls

Having reviewed hundreds of SIR test results, I’ve seen these issues repeatedly:

Condensation Problems: If humidity ramps too quickly, water droplets form on test boards and cause false readings. Use controlled ramp rates and drip shields.

Connector Pattern Failures: The J1 and J2 wave solder connector patterns often show marginal performance even on control boards. This is a known characteristic of the test vehicle design.

Inadequate Sample Storage: Test assemblies sitting in uncontrolled environments absorb moisture and contamination before testing even begins. Store in nitrogen or desiccated cabinets.

Mismatched Materials: Using generic kit boards instead of boards from your actual PCB supplier undermines the entire qualification. Spend the extra money for representative materials.

Where to Get IPC-9202 and Related Resources

Official Sources for IPC-9202

IPC-B-52 Test Kits and Supplies

Related Standards to Consider

IPC-9202 Frequently Asked Questions

What is the difference between IPC-9202 and IPC-TM-650 2.6.3.7?

IPC-TM-650 2.6.3.7 is the underlying test method that describes how to measure SIR. IPC-9202 is a complete test protocol that specifies sample sizes, test conditions, acceptance criteria, and reporting requirements specifically for process qualification using the IPC-B-52 test vehicle. Think of TM-650 as the measurement technique and IPC-9202 as the complete qualification procedure.

Does J-STD-001 require IPC-9202 testing?

J-STD-001 requires demonstrating materials and process compatibility but doesn’t mandate IPC-9202 specifically. However, IPC-9202 is explicitly designed to satisfy J-STD-001’s “objective evidence” requirement for electrochemical compatibility. It’s the most widely accepted method for this purpose.

How many test boards do I need for process qualification?

IPC-9202 requires a minimum of 10 processed test assemblies plus 2-3 unprocessed controls for formal process qualification. For process characterization (comparison studies), 3 assemblies may be sufficient.

Can I use test boards from a kit instead of my actual PCB supplier?

Technically yes, but this undermines the value of testing. The entire point of IPC-9202 is evaluating your specific material set. If you use generic kit boards with different solder mask, surface finish, or laminate than your production boards, the results don’t represent your actual process.

What if only one pattern fails on one board?

IPC-9202 doesn’t specify statistical acceptance criteria—that’s left to the user and their customer requirements. However, a single failing pattern typically indicates a process issue that should be investigated. Review the visual inspection results for that specific location before making accept/reject decisions.

Conclusion

IPC-9202 provides the framework for generating objective evidence that your manufacturing process produces electrochemically reliable assemblies. Combined with the IPC-B-52 test vehicle, it offers a standardized approach that customers, auditors, and quality systems recognize worldwide.

The investment in proper qualification testing is small compared to the cost of field failures or customer requalification demands. If you’re building anything that operates in humid environments—or if your customers require J-STD-001 compliance—IPC-9202 testing should be part of your quality program.

For first-time implementation, I’d recommend getting IPC-9203A alongside IPC-9202. The Users Guide provides practical clarification that helps you avoid common mistakes and interpret requirements correctly.