Many processes require the engineered control of electrostatic discharges (ESD) to prevent damage to electrically sensitive equipment and analytic processes, as well as to prevent fire or explosion when handling flammable liquids, powders, and gases. Reduction of static charges by effective grounding is an important factor in maintaining a safe environment and protecting test equipment. An engineered ESD flooring material provides an economical and effective means to ground personnel without having to rely on hard point grounds such as wrist straps.
The selection of an ESD control flooring surface depends primarily on the intended use of the facility, and should begin with a thorough evaluation of the type of activity to be performed. There are two primary types of standards: those that handle sensitive electronic devices and equipment and those that control hazardous environments. In addition, the practical requirements of the flooring system, such as wear and chemical resistance, need to be matched with the electrical requirements.
Static charges in environments where the intended use is the handling and processing of flammable liquids, powders, and gases pose a significant threat to the safety of the personnel within the facility and, of course, the facility itself. National Fire Protection standard NFPA 77-14 Recommended Practice on Static Electricity details the safe conditions and procedures for handling hazardous materials in respect to electrostatic discharges and effective grounding. The ESD flooring and personnel footwear should be thoroughly evaluated in conjunction with the building ground system as part of any general safety program.
There is a wide variety of products for ESD control floor surfaces. Careful consideration should be given to present and future requirements. Each type of material will have advantages and disadvantages in different environments and intended uses:
- Resilient ESD tile and sheet goods
- ESD carpet
- Two component ESD epoxy floor paints
- ESD waxes and other topical treatments
- Polymer ESD coatings
For a detailed description of each of these materials, click here.
This Cleanroom Tip was taken from “ESD Control Flooring in Clean Environments,” by Erik S. Van Anglen. The article originally appeared in the January 2014 issue of Controlled Environments.