--- title: "Conductive vs. Dissipative ESD Trays | Termotray" description: "Conductive vs. dissipative ESD trays by application: where insulative material fits, typical resistance ranges, and what to check on incoming material." url: "https://www.termotray.com.br/en/library/conductive-vs-dissipative" type: "article" published: "2026-10-22" updated: "2026-10-28" author: "Amilcar Luchesi" --- # Conductive or dissipative: how to avoid overpaying The three classes of electrostatic discharge (ESD) material, how each one handles charge, and why choosing by application avoids unnecessary cost. [Specify It Right](https://www.termotray.com.br/en/library/category/specify-it-right) · 6 min read · Published October 22, 2026 · Updated October 28, 2026 ## Key takeaways - Conductive and static dissipative materials are chosen by application; neither class is better than the other. - A conductive tray drains charge quickly. A dissipative tray releases charge gradually and in a controlled way, and in many cases that's all the component needs. - Because conductive material costs more, define the class with our engineers before you request a quote. - At incoming inspection, the class is confirmed by the material's technical data sheet (TDS) and a surface resistance measurement. Conductive or dissipative? It depends on the application. A conductive tray drains charge quickly; a dissipative tray releases it gradually and in a controlled way, and in many cases that's all the component needs. Because conductive material costs more, it's worth confirming the class with Termotray's engineers before you request a quote. Below are the three classes of electrostatic discharge (ESD) material and when to use each one. ## What are the conductive, dissipative, and insulative classes? An ESD material's class is defined by its surface resistance, measured in ohms (Ω). ANSI/ESD S541, the reference standard for ESD protective packaging, classifies materials by this behavior: the lower the resistance, the more easily charge moves across the tray and drains to a grounded point. In our work, we use these typical ranges as a reference. - Conductive, 10⁴ to 10⁶ ohms: drains charge quickly. - Dissipative, 10⁶ to 10¹¹ ohms: releases charge gradually and in a controlled way. - Insulative, above 10¹¹ ohms: holds charge and needs special precautions near ESD-sensitive components. In practice, a conductive tray is usually black, with carbon compounded into the resin. Insulative material is plastic with no anti-static treatment, such as standard clear PET. Dissipative material sits in the middle range and is usually made with additives that lower resistance without reaching the conductive range. The class is one of the decisions covered in our [guide to specifying trays by life cycle](https://www.termotray.com.br/en/library/specify-trays-by-life-cycle), along with material, wall thickness, and how long the anti-static protection needs to last. ## How does each class handle charge? On a conductive tray, charge moves almost instantly. When the tray touches a grounded workbench or the hand of an operator wearing a wrist strap, the accumulated charge drains away in a fraction of a second. That matters when an exposed component can't tolerate static charge sitting on its packaging. On a dissipative tray, the charge also drains, but gradually and in a controlled way. For some sensitive components, a slower discharge reduces the peak current when a charged part touches the packaging. That's why lower resistance doesn't necessarily mean more protection for every component. Insulative material holds charge. Charge generated by friction, when a part slides into a cavity or stacked trays are pulled apart, stays where it formed. Near sensitive components, this material needs special precautions, because the electric field of a charged surface can induce charge on a component even without direct contact. Related solution [ESD trays](https://www.termotray.com.br/en/solutions/esd-trays) Conductive or static dissipative, in the appropriate ESD class for your application. ## When does the application call for conductive, and when is dissipative enough? Conductive trays are usually recommended for highly sensitive exposed components, such as bare die, memory modules, and assembled PCBs (PCBAs) with exposed components. That's especially true when the tray is used in an ESD protected area (EPA) with grounded workbenches and operators. Conductive is also the choice when your customer's packaging specification calls for the conductive class. Dissipative trays work for many applications with PCBAs, connectors, sensors, and modules. They prevent charge buildup and release charge in a controlled way, which in many cases is enough for handling and in-plant transport. Encapsulated parts, on the other hand, often don't need ESD protection, and insulative material may be the better choice for them. The decision weighs three factors: the component's sensitivity, as stated by its manufacturer; the environment the tray moves through; and your customer's requirements. In electronics manufacturing, those requirements are usually spelled out in the customer's packaging specification. For [ESD trays](https://www.termotray.com.br/en/solutions/esd-trays), Termotray's engineering team reviews all three before recommending a class. ## Why does the class have such a big impact on price? A conductive tray costs more than an equivalent tray in dissipative material. The difference is mainly in the raw material. Design, geometry, and cavity count can be identical, but conductive-filled sheet usually costs more. That difference repeats with every lot and every reorder. On a high-volume expendable tray, specifying conductive when dissipative would do means paying more on every order, with no added protection for that component. On a returnable tray, the extra cost is spread across many cycles, but it still adds to the upfront investment. The opposite mistake costs money too. Underprotecting exposes the component to [latent damage](https://www.termotray.com.br/en/glossary#dano-latente), which doesn't show up at inspection and surfaces later, often after the part has reached your customer. That's why the class should be set by the application, not by the habit of always ordering the same one. ## How do you confirm the class on the material you receive? The first document is the material's technical data sheet, with the resistance range and the test method. Attach it to the approved tray specification so every lot is checked against the same reference. Incoming inspection uses a surface resistance meter, with the electrodes placed at defined points on the tray, such as the bottom of a cavity and the rim. Humidity and temperature affect the reading, so record the ambient conditions with every measurement and always follow the same procedure. ESD control programs based on IEC 61340-5-1 or ANSI/ESD S20.20 typically call for verifying packaging throughout its service life, not just at purchase. On returnable trays, those checks show when protection starts to drift out of range. Our article on [topical vs. in-resin anti-static](https://www.termotray.com.br/en/library/topical-vs-in-resin-antistatic) explains why that happens. ## What to have ready for our engineers To recommend the appropriate class, we need to understand the component and the path it travels. The more complete the information, the more precise the initial tray proposal. These points usually determine the class. - A drawing of the board or component, showing the exposed areas. - ESD sensitivity data from the component manufacturer, if available. - Where the tray circulates: an ESD protected area, an automated line, or shipping between companies. - Any class requirement in your customer's packaging specification. - The tray's life cycle, from single-use to years of returnable service. With this information in hand, send your request through the [quote form](https://www.termotray.com.br/en/quote). If the class isn't defined yet, we'll review the application and tell you whether conductive is necessary or dissipative is enough. For the other specification decisions, see our guide on [how to specify a thermoformed tray](https://www.termotray.com.br/en/library/specify-trays-by-life-cycle). Typical surface resistance ranges: conductive, 10⁴ to 10⁶ ohms; dissipative, 10⁶ to 10¹¹ ohms; insulative, above 10¹¹ ohms. Confirm the values for each material on its technical data sheet. ## Frequently asked questions ### Can insulative material be used near electronics? Yes, insulative material can be used near electronics when the component isn't sensitive to electrostatic discharge or is encapsulated. Near exposed components, insulative material needs special precautions, because it holds the charge generated by friction and can induce charge on the component even without contact. In those cases, our engineers assess whether dissipative or conductive material is needed. ### How do I check the resistance of a tray I've received? To check an incoming tray, compare the material's technical data sheet with a surface resistance measurement taken with a suitable meter at defined points on the tray. Record the ambient humidity and temperature, which affect the reading, and always use the same procedure so you can compare one lot with another. ### Does black mean a tray is conductive? Not reliably. Color alone doesn't prove that a black tray is conductive. Conductive trays are usually black because of the carbon, but some black trays have no ESD properties, and some dissipative materials come in other colors. The class is confirmed by the data sheet and by measurement, not by appearance. ### Can I switch from conductive to dissipative on a tray I already use? In many cases, yes: a conductive tray you already use can be switched to dissipative material. Termotray's engineers review the component and the process, and if dissipative is enough, the switch can lower the cost of future reorders. Because each material behaves differently in thermoforming, the change is validated with samples before the production run. Author · **Amilcar Luchesi** · Technical Director ## Related reading [Functional trays: how to specify by life cycle](https://www.termotray.com.br/en/library/specify-trays-by-life-cycle) [Topical or in-resin: which ESD protection lasts as long as you need it](https://www.termotray.com.br/en/library/topical-vs-in-resin-antistatic) [Trays for electronics](https://www.termotray.com.br/en/industries/electronics) ## Send us your board drawing, and we'll recommend the appropriate ESD class [Request a Quote](https://www.termotray.com.br/en/quote) --- Termotray is a Brazilian manufacturer of custom thermoformed trays for auto parts, electronics, and sensitive components, based in Guararema, São Paulo. - Request a Quote: https://www.termotray.com.br/en/quote - Site index for AI agents: https://www.termotray.com.br/llms.txt - Instructions for AI agents: https://www.termotray.com.br/agents.md