IEST-RP-CC052.1: Understanding, Identifying and Controlling Electrostatic Charge in Cleanrooms and Other Controlled Environments is a comprehensive document that will be of great use to managers and operators of all cleanrooms.  It is hoped that the information provided will lead the user to be able to apply the fundamentals they learn in the RP to recognize deficiencies in their own environment and lead them to choose appropriate remedies to avoid potential product losses, equipment failures or spurious particle events.  The focus and scope of this RP is much different and more comprehensive than IEST-RP-C022: Electrostatic Charge in Cleanrooms and Other Controlled Environments, which has now been archived. In IEST-RP-CC052, a different approach was taken to provide cleanroom personnel with the background necessary to understand the science of electrostatic charge phenomena and thus understand the basis for charge control protocols. 

Electrostatic charge is a contaminant of energy that is rarely understood by those responsible for and working in cleanrooms.  Typically referred to as ESD in most lab and manufacturing environments, it can be controlled through grounding of all conducting objects in the cleanroom including personnel, by eliminating insulators where possible, and by use of ionizers to avoid damage to products as workers sit and work at assembly or test benches.  

However, in cleanrooms where people and product typically move around while working and the very nature of cleanroom materials, airflow and low relative humidity in the clean environment generates a myriad of electrostatic phenomena.  The results caused by these phenomena can include electrostatic discharge (ESD) that damages product but also can manifest in other more subtle ways that also can modify the environment causing spurious particle events, interfere with processing equipment, and other problems that can hinder productivity or plague equipment maintenance efforts.

Since it is impossible to see electrostatic charge and its associated manifestations, one must be knowledgeable in the science that creates it and be able to analyze the environment to discover weakness that allows the electrostatic event to develop and play out. 

First printing: August 2021

Document prepared by Working Group 052 of the IEST Contamination Control Division (WG-CC052).