What is UL 1634

UL 1634, also known as the Standard for Safety of Fire Tests of Through-Penetration Firestops,

is a test standard set by Underwriters Laboratories (UL) to evaluate the fire performance of

through-penetration firestop systems in buildings. These systems are designed to seal openings

created when pipes, cables, or other elements penetrate fire-rated walls or floors, preventing

the spread of fire and smoke.

Fire Testing and Criteria

The UL 1634 test evaluates the fire resistance of through-penetration firestop systems based on

their ability to prevent the passage of flames, gases, and heat. The test subjects the firestop

assemblies to various conditions, including exposure to high temperatures exceeding 1900

degrees Fahrenheit, as well as air pressure and water sprays. The aim is to ensure that the

firestop system can maintain its integrity during a fire and effectively contain it.

Test Procedure and Requirements

To meet the requirements of UL 1634, a through-penetration firestop system must undergo rigorous

testing. The test involves constructing a mock wall or floor assembly with the penetration

opening. The firestop material is installed according to the manufacturer's instructions, and

then subjected to the fire test. The system is evaluated based on factors like flame spread,

smoke leakage, temperature rise, as well as structural stability and duration of protection.

If the system passes all the criteria outlined in UL 1634, it is considered compliant.

Importance of UL 1634 Compliance

UL 1634 compliance is essential for ensuring the safety of occupants in buildings. Through-penetration

firestop systems play a critical role in containing fires, allowing people to evacuate safely and providing

time for firefighters to respond. By adhering to the standards set by UL 1634, manufacturers can provide

firestop solutions that have demonstrated their effectiveness in real-world scenarios. Additionally,

compliance with UL 1634 may be required by local building codes and regulations.