October 20, 2022
Electrostatic Dissipative (ESD) floors are floors that are grounded to dissipate or neutralize electrostatic discharges. ESD floors are required in any facilities that manufacture, process or transport electronic parts, assemblies, and equipment that are susceptible to damage from electrostatic discharge.
So what does that really mean? Read on to learn a little history, standards, and why and where ESD floors are required.
History
In the early 1980s, as the world was increasing its reliance on technology, the costly and potential dangers from static discharge on electronic components was of growing concern. The costs associated with damaged electronic devices from electrostatic discharge could be as little as a few cents, however, when the loss of production and costs for repair and rework, shipping, labor, and overhead are also calculated — costs could be in the hundred or thousand dollar ranges.
The EOS/ESD Association, Inc. was formed to address the protection of sensitive electrical and electronics from electrostatic discharges. Through the association’s research and development, the ESD Association Standard ANSI/ESD S20.20 was created. It covers “the requirements necessary to establish, implement, and maintain an electrostatic discharge (ESD) control program for activities that manufacture, process, assemble, install, transport, package, label, service, test, inspect, or otherwise handle electrical or electronic parts, assemblies, and equipment susceptible to damage by electrostatic discharges greater than or equal to 100 volts human body model (HBM) and 200 volts charged device model (CDM). The CDM voltage level used in this document is based on managing process essential insulators to mitigate field-induced voltages on devices that could lead to damage.”
The EOS/ESD Association, Inc. is the only organization accredited by the American National Standards Institute (ANSI) to write and produce standards on electrostatics.
Important Terms
Before we dive further into ESD flooring let’s review some key terms:
Electrostatic Discharge: The immediate and uncontrolled discharge of electricity between bodies at different electrical potentials. ESD can easily degrade or destroy electronic components and cause equipment malfunction or failure.
Resistance: Resistance is a term that describes the forces that oppose the flow of electron current in a conductor. This resistance is measured in Ohms.
Static Electricity: The electrical charge caused by an imbalance of electrons on the surface of a material. The imbalance of electrons produces an electric field that can be measured and that can influence other objects at a distance. Surfaces charged with static electricity attract dust and other contaminants that can be difficult to remove and may cause damage to sensitive electrical components.
Triboelectric Charge: The charge created by coming together and separation of two materials – such as a person walking across a floor or sliding an electronic device in or out of a plastic bag.
Ground: When a charge can be conducted through a material, the solution to static discharge problems is to provide a path for the charge to flow to ground, thereby neutralizing it. This solution works only for static dissipative and conductive materials.
Human Body Model (HBM): Refers to an electrostatic discharge occurring from a human body to a device that is deemed to be sensitive to the charge. This is the most common cause of ESD damage today.
Machine Model (MM): Refers to an electrostatic discharge occurring from a charged conductive object, such as a metallic tool or fixture, to a device deemed to be sensitive to the charge.
Charged Device Model (CDM): Refers to an electrostatic discharge coming from an ESD sensitive device, which can frequently occur after the device has moved across a surface or has vibrated in a package during transport. For some electrical devices, a CDM can be more destructive than a HBM event.
Anti-Static Materials- Anti-static materials suppress the initial electrostatic charge and have an electric resistivity generally between 1010 and 1012 ohms/sq.
Conductive Materials: Conductive materials have low electrical resistance, and thus allow static charges to flow easily across its surface. These materials generally have less than 105 ohms/sq surface resistance.
Static Dissipative Materials: Static Dissipative materials also allow charges to flow across their surface, but have much greater electrical resistance than conductive materials, thus controlling the flow of the charge and significantly slowing it. This causes the static charge energy to dissipate as heat. These materials typically have between 105 to 1012 ohms/sq surface resistance.
Insulative Materials: Insulative materials will physically insulate or “freeze” static charges on the surface of the material and not allow them to flow. They hold the charge in the material. Anything with a surface resistivity greater than 1012 ohms/sq is considered insulative and will not conduct charges. For this reason insulative materials are not used in ESD protection.
For a full list of terms visit the EOS/ESD Association, Inc. website to download a complimentary copy of ESD Association Advisory for Electrostatic Discharge Terminology – Glossary.
What Are ESD Floors?
Think about how much static electricity can be generated by simply walking on a carpet. The small charge from this static electricity can be enough to damage some electronics. In fact, electrostatic discharge occurring from the human body, (HBM), is the most common cause of ESD damage. ESD flooring was developed to prevent this.
ESD floors are grounded to dissipate or neutralize electrostatic discharges. ANSI/ESD S20.20 sets the criteria for dissipative flooring material as: “a floor material that has a resistance to ground of greater than 106 ohms and less than or equal 109 ohms.”
Where Are ESD Floors Used?
The areas where ESD floors are installed are referred to as ESD Protected Areas (EPAS). EPAS are specifically created to control ESD by keeping all surfaces, objects, people, and electrostatic discharge susceptible devices (ESDS) at the same electrical potential.
ESD flooring should be installed anywhere that ESDS items are being manufactured, processed, handled, etc. According to ANSI/ESD S20.20-2021 these items “include, but are not limited to, microcircuits, discrete semiconductors, thick and thin film resistors, hybrid devices, printed circuit boards, and piezoelectric crystals.”
Some common places ESD Protected Areas are installed:
- Data Centers
- Processing Areas
- Clean Rooms
- Packaging Lines
- Laboratories
- Plastic Manufacturing
- NMR Rooms
- AGV Warehouses
- Electronics Assembly
- Pharmaceutical Facilities
- Electric Vehicle Manufacturing Plants
- Aerospace Manufacturing Plants
Solutions for ESD Flooring
Resinous flooring is an ideal choice for areas requiring ESD flooring. Often times, the additional features and benefits of seamless flooring, such as hygiene, chemical and wear resistance, slip resistance, and the ease of maintenance, make resinous flooring the best choice.
Dur-A-Flex has been dedicated to manufacturing quality resinous flooring systems for over 55 years. Our options for ESD flooring include:
- Armor-Stat ESD
- Dura-A-Gard ESD
- Cryl-A-Stat ESD
Each of these ESD flooring systems meet the ANSI/ESD S20.20 standards for static dissipative flooring by providing resistance to ground greater than 106 ohms and less than or equal 109 ohms. Each also offers their own unique additional features and benefits.
When deciding which ESD flooring system to choose, we advise discussing the project with your local Dur-A-Flex representative. They will work with you to review additional environmental considerations before making a recommendation.
Recap:
The ESD Association Standard ANSI/ESD S20.20 requires electrostatic dissipative flooring is installed in any area that electrostatic discharge susceptible items are being manufactured, processed, handled, etc. Dur-A-Flex offers 3 exceptional options for ESD flooring.
Author: Jes Grant
Jes Grant is the content development manager for Dur-A-Flex. She has over 15 years of experience creating content for various technical industries, and has been featured in several publications for her writing and design work.