Technical cleanliness

Technical cleanliness concerns itself with the amount of residual dirt on the surface of cleanliness-critical components. The analysis and risk assessment of particulate, ionic and/or film contamination is playing an ever greater role for the quality and reliability of mechanical, electrical, and electronic components. The aim is to specify and implement technical cleanliness in such a way that the unavoidable amounts of residual dirt cannot cause malfunctions.

Knowing the permitted amount of residual dirt, its analytical determination in manufacturing and assembly, and risk management with actions all have the same goal: to prevent functional failures and the insufficient implementation of requirements (e.g. minimum operating time) for systems and components.

Technical cleanliness concerns itself with requirements for:

Mechanical systems and their manufacture

Assembly processes

Electronics production

Risk-based prevention and detection actions aim to manage the following physical and chemical contributors towards malfunctions:

Fluff

Fibers

Nonmetallic particles

Metallic particles

Ionic contamination

Film contamination

The motivation is preventing inadmissible:

Mechanical damage

Leakage currents

Arcing

Electrical isolation for contacts

Electrochemical migration (ECM) due to hygroscopic particles

Author: Winfried Dietz, Dietz Consultants GmbH