How to Determine if an HVAC Tape is UL Compliant

By: Team Tape University®

April 28, 2022

AF 99 UL Listed HVAC Tape

UL listing identifies if a tape is suitable for HVAC installation.

If you’re doing HVAC work, including installation and maintenance of insulation, it’s vital that you use UL-listed tape for a few reasons. First, it guarantees that the tape is tested in order to prevent tape failure. Second, it provides a quick visual confirmation to inspectors that correct tape has been used. Finally, it helps to achieve full system closure when properly applied. But how do you know tape is UL listed?

How to Find Out

There are two easy ways to determine if tape is UL listed. First, check the packaging if the tape is unopened. There should be a small “UL listed” symbol on the packaging. If the tape is opened, try looking at the tape itself. Most HVAC tapes will show the UL mark on the non-adhesive side of the tape. Some types might also show this on the tape core.

Types of UL Listings

There are two main types of UL listing to look for on HVAC tape: UL 181A-P Listed and UL 181B-FX Listed.

  1. UL 181A-P is used to seam, seal and join rigid fiberglass duct board, flexible air duct, and sheet metal. It is made of aluminum or aluminum alloy foil and has a minimum width of 2.5 inches. As an acrylic adhesive, it has an aggressive nature; accordingly, most UL 181A-P foil tapes have a release liner. This tape is strong enough to withstand the vast thermal cycles of any HVAC system.
  2. UL 181B-FX should only be used on Class 1 Flex duct. The primary function of this type is to seam, seal and join HVAC materials. These tapes have to be foil, film or cloth and have a maximum width of 1.88 inches. Some UL 181B-FX tapes can be substituted for traditional paint-on mastic.

Make sure you choose the UL-listed tape that is right for your project. The UL listing is a guarantee that the HVAC tape can stay in place for the life of the system when properly installed, but it’s up to you to make sure you’ve selected the appropriate tape for the job.

To find the perfect HVAC tape for your job, visit shurtape.com.

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