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Frequently Asked Questions


Engineering judgments. What are they?

A specific drawing or group of drawings created by a firestop manufacturer for a customer for a specific firestop application on a job-site.

Why do they exist?

No matter how many firestop tests are completed at UL/OPL, contractors seem to always encounter different ways of penetrating fire-rated assemblies. In order to provide the proper fire protection for an entire building, custom drawings are needed for these odd applications.

How are these drawings created?

Engineering judgments are based off of UL/OPL tested systems. These designs are created by a qualified technical personnel in accordance with the "Recommended International Firestop Council (IFC) Guidelines for Evaluating Firestop Systems Engineering Judgments" in mind.


To what temperatures are the firestop products tested to?

The firestop products are tested to the standard time/temperature curve when tested to UL 1479 or UL 2079. The standard time/temperature curve is as follows:

1000°F at 5 min.
1300°F at 10 min.
1550°F at 30 min.
1700°F at 1 hour
1850°F at 2 hours
2000°F at 4 hours


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