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The Condenser: UL and You

In this Condenser article, we discuss UL and what they do for life safety products. UL sets the standards and defines the tests for fire and smoke dampers.

You may have noticed their logo on your wall plugs. Maybe there’s a circle with the letters “UL” on the back of your tablet. You’ve probably seen it on your smoke detectors and your dampers, too. What is UL? What do they do?

Underwriters Laboratories (UL) is an organization that tests the safety and security of products used by the public every day. UL-approved labs test these products based on their design and intended purpose, in accordance with their stringent testing standards. These tests will determine whether the product is safe for regular use. Products that pass these tests, and meet UL's standards for safety, will receive a classification. A product with the "UL" logo signifies that the product is safe to use.

For life safety products, such as smoke detectors and fire dampers, UL tests ensure the product will perform during an emergency.

All life safety dampers are tested and certified by UL.

Life safety dampers must pass the tests set forth by UL to be approved for use in a passive fire protection system. Fire dampers must pass the tests described in UL 555, while smoke dampers have to pass the tests in UL 555S. These tests put each damper through the ringer:

  • Fire dampers must withstand temperatures of 1792°F or more for up to three hours and must fully close at the end of the time,
  • Smoke dampers are opened and closed 20,000 times, in a cycle test, to make sure they will operate in an emergency regardless of wear and tear,
  • Damper actuators must undergo their own set of tests before they can be installed on a life safety damper,
  • Combination fire-smoke dampers must pass every test in UL 555 and UL 555S to be approved for use in both situations.

UL defines these test standards to ensure that all tested products are ready to respond during a crisis. When you see the UL seal on a life safety product, you know its been tested to work safely during an emergency. You can trust that your life safety dampers will close when they need to.

MCDLG & Continuing Education

MCDLG offers free self-paced courses online through AEC Daily. 

Our UL Damper course, Fire & Smoke Protection with Life Safety Dampers, goes over all of the basic stats, terms, and principles involved in choosing life safety dampers for your passive fire protection system.  

Visit AEC Daily to see MCDLG Online Courses

This course provides continuing education credits for a variety of institutions, including ASHRAE's PDUs. Learn the basics of UL dampers and earn credit, at your own pace. Visit the MCDLG course page on today!

Do you have a question on something we haven't covered here? Or maybe you need help from industry experts? MCDLG can help. Contact us by clicking on the button below.

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Mestek Commercial Damper and Louver Group

MCDLG is a collective of top-tier HVAC brands.
  • Arrow United Industries
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We build every louver and damper from the ground up to meet your specifications. Our team works to ensure that you get the best solutions for your project's requirements.

Want to know more? Contact us online through the MCDLG Contact page. We are ready to help!

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