Questions And Answers

Not all ESD footwear that meets the ANSI/ESD S20.20-2007 Table 3 required limit of less than 1 x 10E9 ohms may be suitable as the footwear component to meet the Table 2 Flooring / Footwear System – Method 1 required limit of < 3.5 x 10E7 ohms tested per ANSI/ESD STM97.1.

For example in ESD SP9.2-2003 Footwear - Foot Grounders Resistive Characterization (not to include static control shoes) APPENDIX E has Foot Grounder Classifications. To meet ANSI/ESD S20.20 Table 2 Flooring / Footwear System – Method 1, one would want to use Foot Grounder Standard Use Type A which has the Resistance Value of .0 X 10^5 to 3.5 X 10^7 ohms.

However, ANSI/ESD S20.20 Table 2 Flooring / Footwear System has a Method 2 which for product qualification has two tests (both required). The resistance required limit is increased to < 1.0 x 10E9 ohms tested per ANSI/ESD STM97.1 if passing the required limit of < 100 volts tested per ANSI/ESD STM97.2.

ANSI/ESD STM97.1 is Floor Materials and Footwear - Resistance Measurement in Combination with a Person and ANSI/ESD STM97.2-2006 Floor Materials and Footwear- Voltage Measurement in Combination with a Person.

After product qualification, the only ongoing compliance verification test is < 10E9 ohms per ESD TR53 which can be performed using a regular Footwear Tester.