We learned something very valuable from our fire testing experience with Underwriter’s Laboratories—our products work!
As we stated before, if products are to be approved specifically for excessive clearances, they must be tested with excessive clearances. So, that is exactly what we did! Not once, but twice!
In the development of our Crown Fire Door Products, we purchased wood fire doors made, specifically with excessive clearances, then applied our Fire Door Stop to the doors for testing. Because we wanted a 90-minute rating, the doors would actually burn for 90 minutes, then undergo a hose stream test. During this first test, it was clear the doors would never make it to 90 minutes. Wood doors shrink in a fire situation, and with burn through, we stopped the test at 60 minutes, hoping all would not be lost, however the door broke apart during the hose stream test. The wood doors had not passed.
We did get a 180-minute rating for steel doors that day, and learned that in order to get a wood door rating, we needed some extra protection where the doors were the most vulnerable: the edges. This is when our Crown Fire Door Stop really developed into a System. Different elements go together for different clearance issues on different doors. For wood, we needed to add steel edge protection, more intumescent, and at the same time, developed an Extension to correct excessive undercuts on both wood and steel doors.
With our second fire test, we had complete success; 90- minute ratings for wood doors for all parts of the System—the Fire Door Stop, the Fire Door Extension, and the Crown Latch Protector. We applied our Crown Products to wood doors with generous excessive clearances and received 90-minute ratings all around. We will never forget standing inches from the fire doors, with fire registering over 1500 degrees, raging on the other side of the door! We marveled at how well our products work! Property will be protected, lives may be saved!
We are proud that our Crown Fire Door Stop System will ensure the fire door assembly’s performance as an integral part of a life safety protection system, able to compartmentalize fire, as intended, providing excellent barrier management.