Most people don’t consider just how much dust is circulating in the air or lying on the ground at every second. But when you’ve got sensitive electrical or electronic devices to protect, you’ll quickly realize how big of a threat dust can be. Protecting your device with a NEMA dust tight electrical enclosure from Polycase is the best way to mitigate the risk of dust exposure. But to choose the right dust tight enclosure, you need to come prepared with the answers to some critical questions.Here are some of the most important questions about NEMA dust tight enclosures that our customers ask, with answers from the enclosure experts at Polycase.  
electronics enclosure on outdoor pole

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1. Why do I need a NEMA dust tight enclosure?

Dust can be a threat whether your device is indoors or outdoors. The dust you’ll find in common commercial and industrial settings can contain any of numerous types of substances, from metal shavings to human and animal skin and hair. When it accumulates, dust can cause serious mechanical problems, including blocked vents and overheating. NEMA ratings are the most commonly used rating system for electrical enclosures in the U.S. One aspect that NEMA ratings evaluate is the protection that an enclosure provides from the ingress of dust. Thus, a NEMA dust tight enclosure is one that has a NEMA rating sufficient for complete protection from dust ingress. 

2. What are the dust tight NEMA ratings and dust tight IP ratings?

For indoor applications, a NEMA 12 enclosure is considered to provide dust tight performance. For outdoor applications, a NEMA 3R enclosure,  NEMA 4 enclosure or NEMA 4X enclosure is typically the recommended minimum rating for a dust tight enclosure. When it comes to dust tight IP ratings (another common enclosure rating system), just look for an IP rating that begins with a 6 (such as an IP65 enclosure or IP67 enclosure.) This indicates that the enclosure is designed to be completely dust tight. See our dust proof IP rating guide for more details. 

3. What features make an enclosure dust tight?

An enclosure gasket is one of the most important features for creating a dust tight enclosure. Gaskets are rubber or foam strips that help seal an enclosure against liquid or solid ingress. You’ll typically find them where two parts of an enclosure join together, such as the enclosure door or cover, front panel or access panel. In addition, enclosures should be designed to fit together as precisely as possible. Precise manufacturing tolerances and high-quality design provide less space into which dust can enter. That’s why Polycase offers NEMA dust tight enclosures that are manufactured to a high standard of dust proof performance. 

4. What materials are suitable for a dust tight enclosure?

Dust tight NEMA electronic enclosures are available in a wide range of different enclosure materials. Polycase offers the following options: 
    • ABS plastic
    • Polycarbonate plastic
    • Carbon steel
    • Stainless steel
  • Aluminum
electrician pulling wire from electronics box

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5. What are some popular NEMA dust tight enclosure options from Polycase?

Polycase has numerous dust tight enclosure options with a variety of NEMA and IP ratings. Here are some of our best dust tight enclosures:

6. How do I know that an enclosure is actually dust tight when it says it is?

That’s a great question that you should always ask when choosing a NEMA enclosure. NEMA ratings are voluntary and not enforced by any government or organization, so you should always look for UL certification along with a NEMA rating. UL certification indicates that the device has been tested by the safety experts at UL to ensure that it meets the standards that its manufacturers claim. Polycase always certifies our dust tight enclosures with UL to guarantee that they perform at the level that our customers require. To look up testing data for any Polycase enclosure, find the UL file number of the enclosure series in the enclosure’s product description. Then, just enter the file number into UL’s Product iQ database to see details on its testing and performance. 

7. If I create cutouts on my enclosure, will it still be dust tight?

An enclosure that has custom enclosure cutouts added may not meet the same NEMA or IP rating as the stock enclosure. If you plan on adding cutouts to your enclosure, it’s important that you take steps to seal any gaps created, such as using the appropriate enclosure accessories. Here’s an example: Cable pass throughs are among the most common types of enclosure cutouts. To ensure that an enclosure with cable pass throughs stays dust tight, device designers and builders use cable glands. These molded plastic devices surround the cable and ensure that solids and liquids can’t enter the enclosure. electrician working on heavy power supply line

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Polycase is always happy to help our customers find the NEMA dust tight enclosure that’s just right for their needs. We’d love to hear from you—just call us at 1-800-248-1233 or contact us online. 
In NEMA Rated Enclosures