ESD and conductive plastic pallets: ohm classes, standards and testing
In briefAn ESD (anti-static) pallet is made of plastic that has been rendered conductive or dissipative: under IEC 61340-5-3 it is conductive below 10⁴ Ω and dissipative from 10⁴ to less than 10¹¹ Ω. You need one where sensitive electronic components are handled, and it only works if the work area is earthed.
An ordinary plastic pallet is an insulator: it picks up a charge through friction and holds on to it, and that charge can damage a sensitive electronic component. An ESD pallet, often called anti-static, is made of plastic rendered conductive so that the charge drains to earth in a controlled way.
Resistance classes in ohms
The figure that matters is resistance, measured in ohms (Ω). For ESD packaging, IEC 61340-5-3 uses three classes [1]:
| Class | Surface or volume resistance | In practice |
|---|---|---|
| Conductive | below 10⁴ Ω (10 kΩ) | the charge drains quickly |
| Dissipative | from 10⁴ to less than 10¹¹ Ω (100 GΩ) | the charge drains gradually |
| Insulative | from 10¹¹ Ω upwards | the charge stays: keep it out of the protected area |
The word 'anti-static' does not appear among these classes. It is widely used but has no precise meaning, and the authors of IEC 61340-5-1 advise against it [1]. When you are offered an 'anti-static pallet', ask for the figure in ohms.
Two examples from catalogues:
| Model (manufacturer) | Stated resistance | Test standard given | Static | Dynamic |
|---|---|---|---|---|
| Euro pallet 1200×800 ESD, PP with ESD compound (Transoplast) [7] | 10³ to 10⁵ Ω | IEC 61340-2-3 | 3,000 kg | 1,000 kg |
| H1 ESD (WERIT) [8] | less than 10⁶ Ω | DIN IEC 61340-5-1 | 5,000 kg | 1,000 kg |
Both fall between conductive and dissipative.
ESD standards: IEC 61340-5-1 and 61340-5-3
IEC 61340-5-1 sets the requirements for an ESD control programme. The current edition is 3.0, published in 2024 [2]. It applies to anyone who manufactures, assembles, packs, transports or handles components with a withstand voltage of 100 V in the human body model (HBM) and 200 V in the charged device model (CDM) [2]. IEC 61340-5-2 is the user guide and is advisory only [3]. IEC 61340-5-3 classifies packaging [1].
An ESD pallet on its own does not make a protected area. Inside the ESD Protected Area (EPA), work surfaces, shelving and trolleys must have a resistance to earth of up to 1 GΩ [4]. Packaging brought in must not have an insulative outer surface and must let the charge drain to the area's earth [5].
Outside the protected area the rule changes. The component must be in dissipative packaging, itself enclosed in shielding packaging [5]. An open pallet does not shield: it carries ESD containers and bags, it does not replace them.
How a pallet becomes conductive
The base plastic, PP or PE, is an insulator. There are two ways to make it conductive, and they behave differently over time [6].
- Conductive fillers compounded into the material, such as carbon black. High loadings are needed, and the effect is permanent, independent of time and environment [6]. This is why many ESD pallets are black, like the first model in the table above [7].
- Anti-static additives that migrate to the surface. They attract moisture from the air and form a conductive film of water. They work as long as the air is humid, and some, such as glycerol esters, last only one or two months [6].
Humidity also matters for testing. ESD packaging materials are normally qualified at 12% relative humidity, and some low-charging materials lose their properties below about 30% [5]. A pallet with an anti-static additive that passes the test in summer may fail it in winter in a heated warehouse, where the air is dry. Ask at what humidity the data sheet value was measured.
How to measure the resistance of an ESD pallet
Surface resistance is measured with a concentric ring electrode to IEC 61340-2-3. It is not the same as surface resistivity, which usually comes out about 10 times higher [1]. When you compare two data sheets, check that they quote the same quantity.
Two other measurements are useful: point-to-point resistance across the deck, and resistance from the pallet to the area's earth [1]. The methods for periodic compliance verification are in IEC 61340-5-4 [1].
ATEX, food contact, recycled material
ATEX
IEC 61340-5-1 states that it does not apply to electrically initiated explosive devices or to flammable liquids, gases and powders [2]. An ESD pallet protects electronic components. If you work in an ATEX zone, the choice of pallet is up to whoever carried out the explosion risk assessment.
Food contact and recycled content
ESD compliance says nothing about food contact or recycled content. If you need either, ask for separate declarations. What to ask for on food is in the guide to hygienic and food-grade pallets; for polymers, see the guide to plastic pallet materials.
What to ask for in the data sheet
- Resistance value in ohms, with the minimum and maximum.
- The quantity measured (surface, volume or resistance to earth) and the test standard.
- Relative humidity at which the test was carried out.
- Technology: conductive filler in the material or anti-static additive.
- Static, dynamic and racking load capacity, as for any pallet: the two models in the table state 3,000 and 5,000 kg static and 1,000 kg dynamic [7][8]. If the pallet goes into pallet racking, where it spans two beams, ask for the racking load capacity too.
- Customisation: some manufacturers offer hot-stamped marking and, on some versions, RFID [8]. What can be added without a new mould is in the guide to custom plastic pallets; for the codes to write to the tag, see RFID pallet tracking.
Read the load capacities using the rules in the guide to plastic pallet load capacity. If the pallet goes into an automated system, the requirements in the guide to pallets for automated warehouses also apply.
Frequently asked questions
What is the difference between an anti-static pallet and a conductive one?
Conductive has a precise definition: for ESD packaging, IEC 61340-5-3 uses it for materials with a resistance below 10⁴ ohms. Anti-static has no threshold, and the authors of IEC 61340-5-1 advise against using the term. If a pallet is sold as anti-static, ask for the resistance value in ohms and the test method.
What resistance should an ESD pallet have?
For packaging, IEC 61340-5-3 sets three classes: conductive below 10⁴ Ω, dissipative from 10⁴ to less than 10¹¹ Ω, insulative from 10¹¹ Ω upwards. In the protected area you need conductive or dissipative materials, never insulative ones. In manufacturers' data sheets, ESD pallets state values such as 10³ to 10⁵ Ω or less than 10⁶ Ω.
Does an ESD pallet stay conductive after years of use and washing?
That depends on how it was made conductive. Carbon black compounded into the material gives a permanent effect, independent of time and environment. Anti-static additives that migrate to the surface depend on air humidity, and some last only one or two months. Ask the manufacturer which technology it uses and measure the resistance at regular intervals.
Do I need an ESD pallet in an ATEX zone?
IEC 61340-5-1 does not answer this question: it states that it does not apply to electrically initiated explosive devices or to flammable liquids, gases and powders. An ESD pallet is designed to protect electronic components. In an ATEX zone, the choice is up to whoever carried out the explosion risk assessment.
Is an ESD pallet enough to protect components?
No. The pallet is part of a system: in the protected area everything must discharge to earth, and trolleys and shelving must have a resistance to earth of up to 1 GΩ. Outside the protected area, components must travel in dissipative, shielding packaging, which an open pallet cannot replace.
Sources
- Electrostatic Solutions, ESD Guide: Definitions (IEC 61340-5-1 and 61340-5-3), updated December 2023
- IEC 61340-5-1:2024 Ed. 3.0, abstract and scope (ANSI Webstore)
- Electrostatic Solutions, ESD Guide: Overview of 61340-5-1 & 2
- Electrostatic Solutions, ESD Guide: EPA equipment
- Electrostatic Solutions, ESD Guide: ESD packaging
- Plastics Engineering, A. Mazo: From Insulator to Conductor, Modifying Electrical Properties in Plastics (24/07/2025)
- Transoplast: 1200×800 solid-deck ESD euro pallet with safety edge (data sheet)
- WERIT: ESD pallets (H1-L ESD data sheet)
Tell us the diameter, weight and destination, and we will point you to the right solution.
Contact us