ESD floor testing: what gets measured, to which standard and how often
Key takeaways
- BS EN IEC 61340-5-1:2024 is the current edition, published in the UK on 30 June 2024. It supersedes the 2016 version. Any specification or test report still citing the undated standard should be checked against the 2024 text.
- 61340-5-1 is an ESD control programme standard. It is not a flooring classification standard, so a floor cannot satisfy it on its own.
- The floor is tested as part of a system. Resistance to ground and point-to-point resistance describe the floor. Where footwear and flooring are the personnel grounding method, the standard sets requirements for the person-footwear-floor system covering both its total resistance and the voltage generated on a person walking across it.
- DSEAR 2002 imposes a risk-based duty to control ignition sources in explosive atmospheres. It does not mandate a conductive floor. A floor may be one of the control measures a risk assessment identifies.
- There is no universal retest interval. Frequency comes from the ESD control programme, the assessed risk and the manufacturer’s requirements, not from a figure someone read online.
Standards references on this page were checked as at 29 August 2026.
What does ESD floor testing actually measure?
Electrical resistance, in two configurations, plus the voltage a person generates while walking. Resistance to ground measures the path from a point on the floor surface to the earth connection. Point-to-point resistance measures between two points on the surface. Walking body voltage measures what actually accumulates on a person as they move across the finished floor in their working footwear.
The first two describe the floor. The third describes the outcome the floor exists to control. Neither displaces the other, because where footwear and flooring are the personnel grounding method the standard carries requirements for both the system resistance and the body voltage. A floor can return textbook resistance figures and still allow an unacceptable body voltage if the footwear, the personnel grounding arrangements or the maintenance regime are wrong. The reverse also holds and both are checked.
Which standard governs ESD floor testing?
Three documents do different jobs and confusing them is the most common error in ESD specifications.
BS EN IEC 61340-5-1:2024 is the programme standard. It sets out the requirements for an ESD control programme protecting electronic devices, covering personnel grounding, equipment, packaging, training, verification and documentation. Flooring appears within it as one element of personnel grounding. It is the document that tells you an organisation is compliant, not the document that classifies a floor.
IEC 61340-4-1:2003+A1:2015 is the test method for measuring the electrical resistance of floor coverings and installed floors. This is the standard a test report should cite when it gives you a resistance figure. It is a method, not a pass or fail threshold.
IEC 61340-4-5 covers the measurement of the person-footwear-flooring system, which is where walking body voltage is determined. This is the test that assesses the combination rather than the floor in isolation and it is the qualification method for a footwear and flooring combination.
One further document is worth knowing about, because specifications routinely miss it. For periodic compliance verification the 2024 edition points to IEC TS 61340-5-4, the technical specification covering compliance verification. Qualifying a footwear and flooring combination to 4-5 and verifying it in service are different exercises and a verification regime written solely against 4-5 is incomplete.
A test report that names a resistance value without naming the method, the electrode arrangement and the conditions is not evidence of anything. Ask which of these standards the testing was carried out to.
What resistance should an ESD floor have?
Two different things get called “the requirement” and separating them is the whole answer. Flooring product literature works to a familiar set of bands: conductive at 10^4 to below 10^6 ohms, static dissipative at 10^6 to below 10^9 ohms and higher resistances above that. Those bands are product and industry terminology describing material behaviour. They are not a classification regime handed down by BS EN IEC 61340-5-1.
What the standard specifies is different in kind. Where footwear and flooring are the personnel grounding method, it sets requirements for the person-footwear-floor system: a total system resistance below 1 x 10^9 ohms and a body voltage below 100 V. Those are system requirements measured with a person in the loop, not a band the floor sits in on its own.
Within that framework, the values written into a particular facility’s ESD control programme reflect the sensitivity of the devices being handled and the working practices in the area. A pharmaceutical wash-down area and an electronics assembly bench are both static-controlled and they are not aiming at the same number. What the programme is doing is tailoring within the standard and setting its own verification limits, not choosing a target freely.
Lower is not automatically better either. A very low resistance floor in an environment where personnel may contact mains equipment introduces a different hazard, which is why the programme considers electrical safety alongside static control.
Why the floor alone cannot demonstrate compliance
This is the single most important point on the page and it is the one most often left out. An ESD floor is one part of an ESD control system. Where flooring is used for personnel grounding, BS EN IEC 61340-5-1 addresses the person-footwear-floor combination rather than the floor by itself, because the current path runs through the operative’s shoes. Static-control footwear, heel straps, the earthing installation and the maintenance regime are all in that path.
The practical consequence is a distinction worth holding onto when you read a certificate. A manufacturer can legitimately state that a flooring system has been tested against particular electrical requirements, or that it is suitable for use as part of a 61340-5-1 personnel grounding arrangement. Both are product statements and both can be true. What no document about the floor can establish is that your facility complies with 61340-5-1, because that is a conclusion about the whole control programme. A certificate that reads as though the floor delivers compliance is claiming something outside its scope.
The same logic applies to DSEAR. DSEAR 2002 places a risk-based duty on the employer to eliminate or control risks from dangerous substances, which includes controlling ignition sources in an explosive atmosphere. It does not name a floor type. Where a risk assessment identifies static discharge as a credible ignition source, a conductive or dissipative floor may be part of the control measures, alongside earthing, bonding, footwear, clothing and procedures.
What affects a test result?
More than most people expect, which is why results are conditioned and why a floor can pass on Monday and fail on Thursday without anything having gone wrong with it.
Relative humidity has a substantial effect on surface resistance, so tests are conducted and reported at stated conditions. Temperature matters. Surface contamination matters a great deal and the usual culprit is cleaning: the wrong polish, a residue-leaving detergent or a maintenance product applied over an ESD floor can materially increase measured resistance and impair the performance the floor was specified for. Curing time matters on a newly laid resin floor, because resistance changes as the system cures.
Earthing is where installation faults tend to surface. The grounding arrangement depends on the flooring system and its design rather than following one universal construction and what the standard cares about is that the installed system delivers the verified performance the programme requires. Where a bond has been left disconnected during a fit-out, resistance to ground readings across the area typically go inconsistent and the pattern of results is often what locates the fault.
How often should an ESD floor be retested?
At the interval set by the ESD control programme. There is no universal figure and publishing one would be inventing a requirement. BS EN IEC 61340-5-1 requires an organisation to have a compliance verification plan and the plan defines what is checked, how and how frequently, based on the assessed risk and the equipment in use.
In practice, facilities commonly verify flooring periodically as part of a wider verification schedule and reassess after events that could change the surface or the system: a change of cleaning contractor or product, a repair, a partial recoat or a change of footwear supplier. Where footwear and flooring are the personnel grounding method, periodic body voltage testing is what confirms the system is still generating less than 100 V, so the walking test belongs in the schedule rather than only at commissioning. A change in the devices being handled is a different case and it may alter how the programme is tailored without the floor itself needing a retest. Commissioning testing at handover establishes the baseline that later results are compared against and skipping it removes the ability to tell drift from a measurement problem.
What documentation proves the floor is doing its job?
A commissioning test report at handover, stating the test method, the electrode configuration, the ambient conditions, the measurement locations and the results against the values in the programme. A record of the earthing installation, including where the bonds are and how the grid is arranged, because the next contractor to work on that floor needs to know. The manufacturer’s product data and any declaration relating to the system installed. Then the periodic verification records generated under the compliance verification plan.
Keep the measurement locations consistent between tests. A floor tested at different points each time produces a set of numbers that cannot be compared, which defeats the purpose of periodic verification.
What to settle before commissioning a static-controlled floor
Establish what the floor is being asked to do and under which regime, because a DSEAR-driven requirement in a solvent handling area and a 61340-5-1 personnel grounding requirement in an electronics facility lead to different specifications. Get the target values from the ESD control programme rather than from a product brochure. Confirm the earthing design before the floor is priced. Agree who carries out commissioning testing and to which standard. Write the cleaning regime into the handover documents and name the products that must not be used.
Static-control resin systems are made by manufacturers such as Sika, Flowcrete, Mapei, Resdev and Remmers and a specialist contractor matches the system, the earthing arrangement and the primer to the values the programme calls for. Listing a manufacturer here does not imply a partnership, approval or accreditation.
For what the products are and how they differ, see anti static flooring explained and anti-static flooring contractors. Related environments are covered on data centre flooring and the wider compliance picture in fire ratings for commercial floors and safety flooring regulations.
Surface Specialists is a network of vetted specialist contractors. Tell us the environment, the values your programme calls for and the earthing arrangement and we match the project to a contractor who works in static-controlled facilities. Get in touch to arrange a site survey. Determining compliance with DSEAR or with an ESD control programme is a matter for the dutyholder and their competent person.
Frequently asked questions
What is the current edition of BS EN 61340-5-1?
BS EN IEC 61340-5-1:2024, published in the UK on 30 June 2024. It supersedes the 2016 edition. Specifications, test reports and product literature still citing the standard without an edition date should be checked against the 2024 text before they are relied on.
What resistance should an ESD floor have?
Two different things are often confused here. The bands quoted in flooring product literature, conductive at 10^4 to below 10^6 ohms and static dissipative at 10^6 to below 10^9 ohms, are industry terminology describing material behaviour rather than a requirement in BS EN IEC 61340-5-1. What the standard specifies, where footwear and flooring are the personnel grounding method, is a person-footwear-floor system resistance below 1 x 10^9 ohms and a body voltage below 100 V. The values written into a specific facility’s programme are tailored within that framework according to the sensitivity of the devices handled and the working practices in the area.
Does DSEAR require a conductive floor?
No. DSEAR 2002 imposes a risk-based duty to eliminate or control risks from dangerous substances, including ignition sources in explosive atmospheres. It does not specify a floor type. Where a risk assessment identifies static discharge as a credible ignition source, a conductive or dissipative floor may form part of the control measures alongside earthing, bonding, footwear and procedures.
Can a floor on its own be compliant with BS EN IEC 61340-5-1?
No. 61340-5-1 is an ESD control programme standard covering personnel grounding, equipment, packaging, training and verification. Flooring is one element within it and where the floor is used for personnel grounding the standard addresses the person-footwear-floor combination rather than the floor alone. Compliance is a property of the programme.
How often does an ESD floor need retesting?
At the frequency set by the compliance verification plan within the organisation’s ESD control programme. There is no universal interval and the standard does not create one. Reassessment is warranted after changes that could affect the surface or the system, including a repair, a partial recoat, a change of cleaning product or contractor or a change of footwear. The 2024 edition points to IEC TS 61340-5-4 for compliance verification testing rather than to the qualification method in 61340-4-5.
Which standard covers the test method for floor resistance?
IEC 61340-4-1:2003+A1:2015 covers the measurement of electrical resistance of floor coverings and installed floors. IEC 61340-4-5 covers measurement of the person-footwear-flooring system, which is where walking body voltage is determined and which qualifies a footwear and flooring combination. For periodic compliance verification the 2024 edition of 61340-5-1 points to IEC TS 61340-5-4. A test report should name the method it used.
Why did an ESD floor fail a retest when nothing changed?
The usual causes are cleaning and earthing. A polish, sealer or residue-leaving detergent applied over the surface can materially increase measured resistance and a disconnected earth bond produces inconsistent resistance to ground readings across the area. Relative humidity and temperature also affect results, which is why tests are reported at stated conditions.
Do data centres need an ESD floor?
It depends on the activity in the space rather than the label on the building. Areas where equipment is handled, built or repaired have a static control case. Sealed racks in a cold aisle involve less handling, but the risk still follows the maintenance work, the personnel movement and the equipment being touched in that area rather than the name given to it. The decision belongs in the facility’s ESD control programme rather than being assumed from the building type or the zone label.