What can we help you with?
Technical flooring, delivered directly
- ESD flooring, urethane cement, terrazzo, and polished concrete
- In-house W-2 installation crews and experienced field leadership
- National service coverage with project-specific staffing plans
- Testing, documentation, and defined project closeout
- Dedicated support for corporate procurement and multi-site contracting
Phone: +1 (844) 687-1961
Our Clients
Routine Verification Resistance Limits
For routine compliance verification of a footwear/flooring system, ANSI/ESD S20.20-2021 identifies resistance below 1.0 × 109 ohms as the maximum allowed value. It also recommends documenting the footwear and flooring resistances measured during qualification that satisfied the below-100-volt body-voltage criterion, then using those resistances for compliance verification.
Craftsman Concrete reviews the facility’s qualification records when planning routine resistance testing and documents the verification criteria in its testing and closeout documentation. This applies to floors installed by Craftsman and other contractors.
Which resistance values should routine checks use?
S20.20-2021 distinguishes the maximum allowed resistance from the values established during qualification (Table 2, footnote 7).
The user should document the resistance values measured for the footwear and flooring system during product qualification that complied with body-voltage generation below 100 volts. Those documented resistances should then be used for compliance verification.
Why resistance alone does not establish body voltage
Lower flooring-system resistance generally means lower body-voltage generation when the person wears appropriate static-control footwear. However, ANSI/ESD STM7.1-2020 identifies other influences in its informative Annex C:
- Footwear used.
- Relative humidity.
- Footwear size and contact surface area.
- Personnel weight and applied force.
- Movement speed.
- Flooring material.
The relationship is a general tendency, so a resistance reading cannot replace the body-voltage measurement.
Initial qualification requires both the system-resistance and body-voltage limits to be met. The S20.20 qualification guide explains how those requirements apply to each combination and its supporting records.
Periodic body-voltage testing is recommended
S20.20-2021 recommends a periodic body-voltage generation test to verify that voltage remains below 100 volts (Table 2, footnote 6).
Periodic testing is recommended, not required by that provision. This differs from initial product qualification, where both Table 2 limits must be met.
Frequently Asked Questions
S20.20-2021 recommends using the documented footwear and flooring resistance values measured during product qualification that satisfied the below-100-volt body-voltage criterion (Table 2, footnote 7). Resistance below 1.0 × 10⁹ ohms remains the maximum allowed compliance verification value.
No. It shows that the measured resistance is below the maximum allowed resistance value. Body voltage also depends on footwear, humidity, contact area, personnel weight, movement speed and flooring material. A resistance reading alone does not establish the body-voltage result.
Table 2, footnote 6 recommends periodic body-voltage testing to verify that voltage remains below 100 volts; it does not make that periodic test mandatory. Initial qualification is different: each footwear and flooring type combination used for personnel grounding must meet both the resistance and body-voltage qualification limits.
Case Studies
Craftsman Publishes 2026–2027 ESD Flooring Technical Guide
ESD Epoxy Flooring Case Study: 34,000 SF Dallas, TX
