Editing Ground (electricity) (section)

== Ground (earth) mat ==
{{Main|Ground mat}}

In an [[electrical substation]] a ground (earth) mat is a mesh of conductive material installed at places where a person would stand to operate a switch or other apparatus; it is bonded to the local supporting metal structure and to the handle of the [[switchgear]], so that the operator will not be exposed to a high differential voltage due to a fault in the substation.

In the vicinity of electrostatic sensitive devices, a ground (earth) mat or grounding (earthing) mat is used to ground static electricity generated by people and moving equipment.<ref>{{cite web| url=http://www.bennettnbennett.com/showResource.cfm?id=22| title=ESD Prevention Measures Part 2: Using Anti Static Mats by Doug Wagner| publisher=Bennett & Bennett| access-date=May 15, 2014| url-status=dead| archive-url=https://web.archive.org/web/20150603162559/http://www.bennettnbennett.com/showResource.cfm?id=22| archive-date=June 3, 2015}}</ref> There are two types used in static control: Static Dissipative Mats, and Conductive Mats.

A static dissipative mat that rests on a conductive surface (commonly the case in military facilities) are typically made of 3 layers (3-ply) with static dissipative vinyl layers surrounding a conductive substrate which is electrically attached to ground (earth). For commercial uses, static dissipative rubber mats are traditionally used that are made of 2 layers (2-ply) with a tough solder resistant top static dissipative layer that makes them last longer than the vinyl mats, and a [[conductive rubber]] bottom. Conductive mats are made of carbon and used only on floors for the purpose of drawing static electricity to ground as quickly as possible. Normally conductive mats are made with cushioning for standing and are referred to as "anti-fatigue" mats.

[[File:3 ply Diagram.jpg|thumb|3 ply static dissipative vinyl grounding mat shown at macro scale]]

For a static dissipative mat to be reliably grounded it must be attached to a path to ground. Normally, both the mat and the wrist strap are connected to ground by using a common point ground system (CPGS).<ref>{{cite web| url=http://www.bennettnbennett.com/productdetail.cfm?prod=18&cat=24| title=Wrist Strap Shown with mat and Common Point Ground System (CPGS)| publisher=Bennett & Bennett| access-date=April 23, 2014| url-status=dead| archive-url=https://web.archive.org/web/20140424211506/http://www.bennettnbennett.com/productdetail.cfm?prod=18&cat=24| archive-date=April 24, 2014}}</ref>

In computer repair shops and electronics manufacturing, workers must be grounded before working on devices sensitive to voltages capable of being generated by humans. For that reason static dissipative mats can be and are also used on production assembly floors as "floor runner" along the assembly line to draw static generated by people walking up and down.