Views: 583 Author: Site Editor Publish Time: 2025-12-05 Origin: Site
### What is UL 10D?
**UL 10D** is the **Standard for Safety for Fire Tests for Door Assemblies and Other Opening Protectives - Draftstopping/Curtain Assemblies**. It is the primary test standard in North America that evaluates the ability of a *deployable* smoke or fire curtain assembly to resist the passage of fire, heat, and smoke **when deployed**.
* **Key Point:** It tests the **fully deployed state** of the curtain, not the stored housing or mechanism. The housing is typically listed under a separate standard (UL 10B for fire doors) or as part of the overall system listing.
### The Test Procedure (Key Requirements)
A curtain assembly is installed in a test furnace and subjected to a severe fire environment following a standard time-temperature curve (similar to other fire tests).
To achieve a **UL 10D rating**, the assembly must meet three main criteria for the duration of its rated period (e.g., 60, 90, 120 minutes):
1. **Integrity (F) - The Most Critical:** The curtain must not develop any openings, holes, cracks, or tears that allow flames or hot gases to pass through. It must remain intact and in its track/channels.
2. **Temperature Rise (T):** The temperature on the unexposed (room) side of the curtain must not increase by more than **450°F (250°C) above ambient** on average, or more than **650°F (360°C)** at any single point. This limits heat transfer and helps prevent fire spread by ignition.
3. **Smoke Leakage (L):** This is often measured as part of the test or under a companion standard like **UL 1784 (Air Leakage Tests)**. The curtain must restrict the passage of cold smoke when subjected to air pressure differentials.
### Common Ratings and What They Look Like
A UL 10D listed curtain will have a label specifying its rating. The format is:
**"UL 10D - X Hour(s) - F/T/L"**
* **Example 1:** `UL 10D - 1 Hour - F/T/L` → A 60-minute rated curtain meeting Integrity, Temperature Rise, and Leakage criteria.
* **Example 2:** `UL 10D - 1.5 Hours - F/T` → A 90-minute rated curtain meeting Integrity and Temperature Rise (may not have a formal L rating but will still provide smoke resistance).
### Importance and Applications
UL 10D certification provides architects, engineers, and code officials with the assurance that the product will perform as a **tested and listed fire protective assembly**. Its applications are defined in building codes (IBC, NFPA 101, etc.) and include:
* **Protecting Large Openings:** Where traditional fire doors or walls are impractical (atriums, open floor plans, performing arts stages).
* **Creating Compartmentation:** Deploying during a fire to subdivide a large space and contain smoke and flames.
* **Protecting Egress Paths:** Used as a **radiation barrier** to protect exit corridors or stairwells from heat radiating across an opening.
* **Shielding External Walls:** In curtain wall applications where the exterior wall doesn't have a sufficient fire rating.
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### UL 10D vs. Other Related Standards (Crucial Distinctions)
| Standard | Purpose | Key Difference |
| :--- | :--- | :--- |
| **UL 10D** | **Fire test for deployable curtains** in their **deployed** state. | Tests the fabric/barrier as a final, static barrier. |
| **UL 10B** | Fire test of **fire door assemblies** (including side-hinged doors). | Often used to evaluate the **housing and head box** of a fire curtain system. |
| **UL 1784** | **Air leakage test** to measure smoke control capability. | Usually performed *in conjunction with* UL 10D to provide the "L" rating. |
| **NFPA 105** | Standard for **Smoke Door Assemblies and Other Opening Protectives**. | The *installation and maintenance* standard that references UL 10D for performance. |
| **NFPA 80** | Standard for **Fire Doors and Other Opening Protectives**. | The primary governing standard for fire curtains; Chapter 20 is dedicated to them. |
### Key Considerations for Specification and Use
1. **Not a Door:** A UL 10D curtain is an **opening protective**, not a door. It deploys automatically upon alarm.
2. **Must Be Part of a Listed System:** The entire installed system must be listed, including the housing, guides, fabric, release device, and controller.
3. **Annual Inspection Required:** Like fire doors, NFPA 80 requires **annual operational testing and inspection** by a qualified professional to ensure reliability.
4. **Deployment and Clearance:** The deployment zone must be kept **completely clear of obstructions** at all times. This is a major life safety issue.
5. **Integration with Fire Alarm System:** The curtain's release must be interconnected with the building's fire alarm/smoke detection system.
**In summary, UL 10D is the definitive fire performance test for smoke and fire curtains. When you see a product listed as "UL 10D," you know it has passed a rigorous full-scale fire endurance test and is a code-compliant solution for dynamic fire and smoke protection.** Always verify the specific hourly rating (e.g., 1 hr) and the suffix (F/T/L) for your project's requirements.