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For UL 864-listed stairway or elevator hoistway pressurizations controllers, check out LFSystems.

🔍 Exploring the Distinction: UL 864 vs. UUKL 🔍

In the world of #highrise life safety, it’s crucial to be aware of nuances that may not be immediately apparent. Today, I’d like to shed some light on a common misconception – the assumption that UL 864 and UUKL are identical, or worse, that UUKL is the only standard for smoke control controllers and systems. In reality, one is a proprietary category designation of a portion of the other.

🌐 UL 864: The Foundation 🌐

Now on its 11th edition, UL 864 is the standard number for the American National Standards Institute (ANSI) & Underwriters Laboratory (UL) standard for “Control Units and Accessories for Fire Alarm Systems”. Currently, there are four Nationally Recognized Testing Laboratories (NRTL) that are accredited by OSHA to evaluate controllers or systems to this standard. These NRTL’s are CSA Group (CSA), FM Global (FM), Intertek (ETL) and UL.

Per its scope, UL 864 covers the requirements of the following:

a) Discrete electrical control units and accessories for fire alarm systems including smoke control, releasing, Building System Information Unit (BSIU), and emergency communication systems;

b) Electrically- and electronically-operated amplifiers that provide speech communication and distinctive sounds in conjunction with fire protective signaling systems; and

c) Commercial stationary and fixed power supplies for fire-protective signaling systems, having input and output ratings of not more than 600 V, direct- and alternating-current, (DC and AC).

💼 UUKL: The Proprietary Designation 💼

On the other hand, UUKL is often mistaken for an independent standard, but it’s actually a proprietary category designation of a single NRTL, Underwriters Laboratory. Researching UUKL at UL’s UL Product IQ®, the requirements state the following.

“The basic standard used to investigate products in this category is UL 864, "Control Units and Accessories for Fire Alarm Systems" (9th ed. or 10th ed.).”

Recognizing the limitation to one NRTL, the National Fire Protection Association (NFPA) is in the process of removing UUKL from 6.4.1 and of NFPA 92, “Standard for Smoke Control Systems”; however, UUKL is being added to NFPA 92’s Appendix — as A.6.4.1 — since UUKL has become synonymous with describing weekly self-testing.

💡 Why Understanding Matters 💡

Recognizing this distinction is vital for ensuring all UL 864-listed controllers and systems are accessible to your project. Updating design specifications and CAD details to require UL 864 for smoke control systems safeguards against any confusion. Informed decision-making empowers the consulting and/or fire protection engineers to choose the right path for their client’s specific needs.

Knowledge and awareness are our allies in achieving industry excellence. Let’s continue the conversation and share insights about the standards landscape. 🚀

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