ANSI/ESD STM97.2-2016 measures the voltage that accumulates on a person walking in static-control footwear on ESD flooring. It evaluates the person, footwear and flooring together as a system. The standard provides procedures for product qualification and for testing installed or applied flooring.
Craftsman Concrete helps facilities define the required footwear/flooring evaluations and assemble the resulting test records into project closeout documentation. Walking body-voltage testing is assigned separately from floor-resistance testing in the specification and testing scope. Our ESD floor testing services explain how testing and reporting can be arranged for your facility.
Identify the testing stage
Product qualification evaluates prepared flooring samples, referred to as specimens in STM97.2, together with footwear under the specified conditioning and test procedure.
Installed-floor testing evaluates the footwear/flooring combination on installed or applied material. Its testing and reporting provisions differ from the qualification procedure. Use the installed-floor walking-voltage testing guide for the applicable test counts, locations and report requirements.
Prepare for product qualification
Select the required measurement equipment
The test uses a hand-held electrode, voltage measurement apparatus, recording device and humidity instrumentation. The apparatus must capture voltage changes during walking within the method’s specified measurement and response characteristics.
The walking body-voltage test equipment guide provides the equipment requirements.
Prepare the flooring assembly and ground connections
Qualification samples must be mounted and grounded according to the method and applicable manufacturer instructions. Floor finishes have their own preparation provisions.
The sample mounting and grounding guide explains the assembly requirements and identifies inconsistent metric and imperial dimensions printed in the standard. Those printed discrepancies should not be treated as resolved fabrication dimensions.
Clean and condition the flooring and footwear
Clean the flooring samples and footwear according to the method’s material-specific preparation requirements.
For product qualification, STM97.2-2016 requires the cleaned floor material and footwear to be conditioned for at least 72 hours at 12% ± 3% relative humidity and 23°C ± 3°C. Keep them in that environment until testing is complete (section 5.2.2.2).
The humidity and conditioning comparison distinguishes this qualification regime from conditions used by other methods and testing stages.
Follow the prescribed walking procedure
Use the starting positions and walking pattern prescribed in Figure 1 of ANSI/ESD STM97.2-2016. The written procedure controls step height, pace, pauses and cycle count. The test continues until the recorded body voltage reaches equilibrium; completing the minimum number of cycles does not by itself establish the endpoint.
The walking cycles and endpoint guide explains these controls.
Informative Annex A discusses alternative walking patterns. Its status and relationship to the prescribed procedure are explained in alternative walking patterns under STM97.2.
Record the required voltage results
For product qualification, perform three tests per sample and report at least the three highest voltages from each test, regardless of polarity: nine readings in total. Summarize the minimum, maximum and mean of their absolute values.
The report also identifies the flooring, footwear, test subject, equipment and test conditions. The reported-voltage values guide explains which readings and summaries belong in the report and how qualification reporting differs from installed-floor reporting.
Interpret the result within the tested conditions
A walking body-voltage result describes the tested person, footwear, flooring and conditions. The prescribed walking pattern does not establish the highest voltage that could occur during every workplace activity.
The guide to interpreting walking-voltage results explains what the standard pattern represents and the limits of extending its results to other activities.
STM97.2 also excludes uses involving electromagnetic interference, ordnance, flammables and explosives. Testing under the method does not guarantee personnel safety. See the separate shock and ignition safety guidance where those concerns apply.
Frequently asked questions
Identify the footwear and flooring combinations to be evaluated, whether the work concerns product qualification or an installed floor, and the governing specification or ESD program requirements. Confirm the required conditions, acceptance criteria and reporting deliverables before testing begins.
No. Floor resistance and voltage generated during walking are different measurements. An STM7.1 floor-resistance result does not supply the body-voltage result measured under STM97.2.