Questions And Answers

Where does it state that ESD footwear is required on each foot?

Per ANSI/ESD S20.20-2007 section 8.2 “For standing operations, personnel shall be grounded via a wrist strap system or by a flooring/footwear system. When a flooring-footwear system is used, one of the two following conditions shall be met:

A. When the total resistance of the system (from the person, through the footwear and flooring to the grounding / equipotential bonding system) is less than 3.5 x 10E7 ohms, Method 1 shall be followed (see Table 2).

B. When the total resistance of the system (from the person, through the footwear and flooring to the grounding / equipotential bonding system) is greater than 3.5 x 10E7 ohms and less than 1 x 10E9 ohms, Method 2 shall be followed (see Table 2 which includes < 100 volt Product Qualification test per ESD STM97.2 Floor Materials and Footwear-Voltage Measurement in Combination with a Person).”

Per ANSI/ESD S20.20 Table 2 Personnel Grounding the test method for Flooring/Footwear System is Compliance Verification ESD TR53.

The Test Procedure using an Integrated Checker includes:

• Place one foot on the integrated checker's foot electrode ensuring the other foot is not in contact with foot electrode or adjacent ESD Flooring. Some integrated checkers may use a dual-foot electrode to allow separate testing of each foot's resistance.
• Repeat for other foot if necessary.

Per ESD Handbook ESD TR20.20 section 5.3.3.3.4 Proper Usage “ESD protective footwear is designed to reduce body charge levels by supplying a conductive path from the body to the floor material. Heel and toe grounders shall be worn on both feet to insure effective use.”