[Building Materials] (Surface-burning Characteristics) Building Units, BLBT

See General Information for Surface-burning Characteristics



This category covers building units, consisting of proprietary mixes of organic and/or inorganic materials formed into panels, blocks, boards, planks, slabs, or sheets fabricated into various sizes, thicknesses and shapes, certified as to surface-burning characteristics.

Some building units are provided with facings or are composites of several materials which may affect the contribution of combustibles under fire conditions. This effect is determined by testing the sample with a longitudinal butt joint, constructed by slitting the facing or by using a factory or field joint (if applicable).

For building units consisting of an interior core material faced on both surfaces, the certification of the product includes the surface-burning characteristics of the core material in addition to the surface-burning characteristics of the finished product.

The certifications are confined to the materials themselves and do not pertain to the structures in which the materials may be installed.

The insulating, acoustical, structural, toxicity of the products of combustion, and other properties have not been investigated.

Authorities Having Jurisdiction should be consulted before installation.


The following product identity appears on the product:

    Building Unit


Building units containing electrical or mechanical equipment are covered under Prefabricated Buildings (QRAR) or Prefabricated Assemblies (QQRX).

For room fire test certification of these products, see Building Units (OERQ).

For the fire-resistance ratings of these products, see Building Units (BZXX).


For additional information, see Surface-burning Characteristics (BIKT) and Building Materials (AABM).


The basic standard used to investigate products in this category is ANSI/UL 723, "Test for Surface Burning Characteristics of Building Materials."


The Certification Mark of UL on the product or carton is the only method provided by UL to identify products manufactured under its Certification and Follow-Up Service. The Certification Mark for these products includes the UL symbol, the words "CERTIFIED" and "SAFETY," the geographic identifier(s), and a file number.

Additional Certification Markings

Products covered under this category are additionally marked with the following information:

+ Flame-spread and smoke-developed values applicable to the product

Alternate UL Mark

The Classification Mark of UL on the product or carton is the only method provided by UL to identify products manufactured under its Classification and Follow-Up Service. The Classification Mark for these products includes the UL symbol, the word "CLASSIFIED" above the UL symbol (as illustrated in the Introduction of this Directory), and the following additional information:

Control No.

+ Flame spread and smoke developed values applicable to the product

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UL, in performing its functions in accordance with its objectives, does not assume or undertake to discharge any responsibility of the manufacturer or any other party. UL shall not incur any obligation or liability for any loss, expense or damages, including incidental or consequential damages, arising out of or in connection with the use, interpretation of, or reliance upon this Guide Information.

Last Updated on 2013-05-16
BLBT.GuideInfo BLBT ACTIVE 20130516 19841214

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