Static Electricity Discharge also known as Electrostatic Discharge (ESD) is one of the most common causes of electronic equipment damage or malfunction. Walking or working on a grounded ESD mat drains the electrical charge before it damages any ESD sensitive devices. There are three types of static control mats that are classified by their surface resistivity range. Surface resistivity is express in ohms (Ω). It measures how much a surface resists draining a static charge. The lower the surface resistivity the faster and more effective the mats will dissipate the Electrostatic charge.