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Home / Assemblies / UL X139
UL X1393-hr Fire RatingBeamLoad-Bearing
Structural SteelMineral WoolDesign

Steel Beam — Spray-applied mineral fiber

UL-listed 3-hour fire-rated steel beam assembly. HSS steel beam with Spray-applied mineral fiber, 3-hour fire rating.

Cross-Section Diagram

12BEAM PROTECTIONSECTION · NOT TO SCALE2 LAYERSsee legend for ① ② ③
Legend
1HSS steel beam(14")
2Spray-applied mineral fiber(1.91")

Specifications

Fire Rating
3-Hour
Load Bearing
Yes
Total Thickness
17.82"
Source / Publisher
UL (Underwriters Laboratories)
Design Number
X139
Assembly Type
Beam
Test Standard
ASTM E119
Construction Group
Non-Combustible
Number of Layers
2 layers

Applicable Codes

IBC 2024 §722IBC 2021 §722

Construction Summary

HSS steel beam with Spray-applied mineral fiber, 3-hour fire rating

Material Layers

LayerMaterialThickness
1HSS steel beam14"
2Spray-applied mineral fiber1.91"

Important Notice

This assembly listing is for reference only. Always verify against the current UL Product iQ database before specifying in construction documents. Material substitutions may void the fire rating. Consult with a qualified fire protection engineer for project-specific requirements.