When in your in the search for exit signs, you may have noticed some numbers and terminology thrown around.
Of these, you may have seen exit signs with a UL 924 listing.
Believe it or not, this is not simply a way to try to sell you on buying these signs. It's in fact a designation given to exit signs that meet certain safety and functionality requirements by a governing body after thorough testing and evaluation.
Yes, even exit signs need certification. This makes sense when you think about the important role they play in emergency situations, guiding people from danger to safety.
Code Compliant UL 924 Listings
The organization that determines if an exit sign is up to muster or not is called Underwriters Laboratories (UL). They are an independent safety organization that was formed in 1894 and is headquartered in Northbrook IL.
To get the certification, products must pass a litany of testing procedures. UL is approved by the U.S. Government's Occupational Safety and Health Administration (OSHA) to carry out this testing. Besides certifying exit signs, they also conduct safety tests on a number of other products, including emergency lights, combo emergency exit signs, and more.
If this wasn't rigorous enough, the UL 924 designation takes into account safety standards set forth by other organizations. Hopefully you like acronyms, because there a number of them that are important to exit sign safety compliance!
IBC, NFPA and ANSI
The UL certification is not something given out to just everyone. Two of most prominent are the International Building Code (IBC) and the National Fire Protection Association (NFPA).
Taking these multi-organizational standards into consideration, the UL 924 Standards Technical Panel (STP) authorizes giving the designation. This panel is composed of representatives from a variety of disciplines, including manufacturers, electricians, architects, engineers, fire departments, and more. When proposals for updating UL listing criteria are received from any of the organizations above, the American National Standards Institute (ANSI) considers them and makes updates as needed.
All this is to say that when you purchase an exit sign that is UL listed or meets all UL 924 guidelines, you can be sure that the quality is at a high enough standard to give you peace of mind.
90-Minute Battery Requirement
Although there are a number of safety and functionality tests that a product must pass in order to receive the UL 924 designation, there are a couple of key requirements. Chief among these is the requirement to have a backup power source that can illuminate the exit sign for at least 90 minutes without main power.
UL 924 makes the 90-minute minimum a nationwide requirement in order to get listed. And for good reason. Exit signs that stay illuminated for up to an hour and a half give enough time for emergency evacuations and procedures to be carried out.
The 90-minute minimum is a requirement of both IBC Section 1011.5.3 and NFPA 101 Chapter 18.104.22.168. Other organizations also mandate this requirement. If an exit sign is installed that cannot meet these requirements, you can be cited on an inspection for non-compliance.
Visibility and Color
Another requirement of UL listed exit signs is that they are tested to have a visibility rating of at least 100 feet. This simply means that, in total darkness, they can be read from that distance. Again, it is not hard to imagine how useful this could be in an emergency scenario. When power outages make a building dark, this illumination standard can save lives.
In addition to this, letters on the exit sign must be either red or green. One reason for this is how we respond to colors. For instance, the human eye is more sensitive to green light, so these signs are easier to see in dark conditions.
The letters on the sign must also be at least 6” high and have a 3/4” letter stroke.
Flammability and Plastic Materials
Since an exit sign needs to be able to operate in emergency situations, it makes sense that it would need to be tested to withstand the flames and heat that it could come into contact with.
The plastic, steel or alumium used to mold UL 924 listed exit signs must meet a polymer count based on mandatory flammability tests. Based on this test, the products are then given one of twelve flame classification ratings.
Where to Buy Your UL Listed Exit Signs
Now that you know all you've ever wanted to know about UL listed exit signs, the only question is where to buy them.
At Exit Sign Warehouse, we have a wide selection of UL Listed signs best fit for your building, whether it is battery assisted, self-luminous types, or more. Each sign meets the highest standards required by UL 924 Listing
Contact us today and our skilled and friendly staff can will answer any questions you have and make sure you are satisfied.