IEC TR 61191-7:2020 PDF

Overview

IEC TR 61191-7:2020 - Printed board assemblies - Part 7: Technical cleanliness of components and printed board assemblies - is an IEC Technical Report that explains how to assess, analyse and manage technical cleanliness in the electronics assembly industry. Rather than setting mandatory limits, it provides practical guidance on sources of particulate contamination (foreign‑object debris), measurement methods, risk assessment and control options for components, PCBs and assembled circuits.

Key topics and technical content

The report covers practical, industry-relevant topics including:

• Definitions and scope of technical cleanliness for components and printed board assemblies.
• Sources of contamination across supply‑chain clusters (electronics manufacturing, passive components, electromechanical parts, PCBs, packaging and logistics).
• Test procedures and measurement methods - e.g., pressure‑rinsing extraction, membrane filter preparation and particle counting - and illustrations of extraction systems and test fixtures.
• Data analysis and metrics such as particle size distribution, Surface Cleanliness Index (SCI), and approaches to data management and visualization for component cleanliness.
• Risk assessment tools to estimate short‑circuit probability from metallic particles, modelling hypotheses and example calculations.
• Process and design controls to reduce particle generation and migration (cleanliness‑controlled design, workplace layout).
• Cleaning techniques and controls (washing, brushing, suction, blowing, adhesive methods) and packaging/logistics recommendations.
• Related contamination topics: filmic contamination, biological or chemical films, and whisker risks.

Practical applications

IEC TR 61191-7:2020 is used to:

• Develop and document contamination control programs for PCB assembly lines and component handling.
• Specify inspection and acceptance testing workflows for incoming components and finished assemblies using particle extraction and membrane analysis.
• Support failure‑mode and reliability assessments by linking measured particulate contamination to electrical risk (short‑circuit probability).
• Create component cleanliness databases and visual reports (SCI trends, particle size distributions) to drive process improvements.
• Guide selection of cleaning processes, packaging and logistics measures to limit foreign‑object debris (FOD).

Who should use this standard

• Quality, reliability and process engineers in electronics manufacturing
• PCB and component suppliers and OEMs
• Test laboratories performing particulate analysis
• Design engineers concerned with contamination‑driven failure modes
• Supply‑chain and packaging engineers working on cleanliness control

Related standards and topics

• References and test method comparisons (e.g., VDA 19 Part 1 style extraction) are discussed in the report. Related subjects include filmic contamination, whiskers, and other IEC/industry documents on PCB assembly and cleanliness control.

Keywords: IEC TR 61191-7:2020, technical cleanliness, printed board assemblies, PCB contamination, foreign-object debris, particle analysis, Surface Cleanliness Index, contamination control.