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USA



There is no Federal Building Code!


  • Each State, and/or in some cases, each local government, decides on its own building codes
    • Further each jurisdiction can adopt older versions, as they desire


  • The International Code Council publishes a model code
    • model document adopted by a jurisdiction with local modifications
    • New revisions published on 3 year 

  • Historically, there were three major code bodies in different geographic regions of USA
    • Building Officials and Code Administration International, Inc. (BOCA)
    • International Conference of Building Officials (ICBO)
    • Southern Building Code Congress International, Inc. (SBCCI)
  • These combined into the International Code Council (ICC) in 1994
    • First edition of uniform model codes published in 2000
    • Consists of building industry players  architects, engineers, trade groups, industry professionals
    • Anyone who is interested!
  • Despite regional historical alignment, each jurisdiction makes its own choice and the result is a mosaic of versions in effect!

  • Does every jurisdiction currently enforcing an ICC Model Code automatically upgrade to the latest edition once it is available?
    • NO, a new edition must be adopted.
    • There are some jurisdictions still using 2000 I-Codes!!


  • Does every state have a uniform state code?
    • NO, some states (Colorado, for example) are prohibited from having a state code. In this case, local cities and/or counties adopt building codes


ICC is not the only Code in existence in US
  • National Fire Protection Agency (NFPA) published their own version after ICC formed
  • American Society or Heating, Roofing, and Air Conditioning Engineers (ASHRAE) has a set of recommended guidelines for energy performance
  • ICC is, however, the most universally adopted



Common Standards (Tests) used in Building Codes:



Roof Tests

Factory Mutual Construction Materials Calorimeter Test (FM 4450)

  • Developed in 1950s for combustible roof assemblies
  • Derived from White House test after Livonia, MI GM plant fire  rapid spread along asphalt on unprotected steel roof deck
  • Measures fuel contribution of foam plastics installed on roof decks
  • Intermediate scale test correlates with the White House test
    • Sample size: 4 ft. long x 4 ft. wide
    • Fire source: Gas burners under deck for 30 min.
    • Test Criteria: Limits on fuel contribution,
    • flame through the roof assembly

UL790 Test Methods for Fire Tests of Roof Coverings (similar to ASTM E 108)

UL-790 is a widely used test method to classify roof covering systems according to their fire resistance originating from sources outside a building. It is applicable to roof coverings intended for installation on either combustible* or noncombustible decks**. The tests include the intermittent flame test, the spread-of-flame test, and the burning brand test for systems installed on combustible decks. Roof Systems are rated as Class A, B or C (with Class A being the most fire resistant and Class C the least).

Class A roof coverings are effective against severe fire test exposures. Under such exposures, roof coverings of this class afford a high degree of fire protection to the roof deck, do not slip from position, and are not expected to produce flying brands.

Class B roof coverings are effective against moderate fire test exposures. Under such exposures, roof coverings of this class afford a moderate degree of fire protection to the roof deck, do not slip from position, and are not expected to produce flying brands.

Class C roof coverings are effective against light fire test exposures. Under such exposures, roof coverings of this class afford a light degree of fire protection to the roof deck, do not slip from position, and are not expected to produce flying brands.

*A combustible deck is formed of wood (sheathing boards or plywood).
**A noncombustible deck is formed of metal, concrete, or poured gypsum.

Intermittent Flame:

Intermittent Flame tests measure the reduction of the roofing material's ability to resist flame penetration, when flame is inconsistent in nature. 3-1/3 ft. (1 m) wide by 4-1/3 ft. (1.32 m) long plywood test decks with the roof coverings in place are positioned at a given slope and subjected to a 1400° F (760° C) flame along the width of the test deck, fanned by a 12 mph (19.3 km/h) air current. The flame is extended approximately two feet beyond the upper edge of the test deck and is applied intermittently, two minutes on and two minutes off, for a total of fifteen cycles. In order to obtain an "A" rating, two roof assembly samples must withstand the 15 cycles and there must be no sustained flame on the underside of the test deck, no production of flaming brands and no displacement of portions of the test assembly. For a Class B, the test assembly is subjected to 8 cycles.

Intermittent Flame Test
Source:
 Western Fire Center, Inc. (WFCi)


Spread of Flame:

Spread of Flame tests measure the reduction of the roofing material's ability to resist the propagation of flame spread. 3-1/3 ft. (1 m) wide by 10 ft. (3.05 m) long plywood test decks with the roof coverings in place are positioned at a given slope and tested using the same flame parameters, but the flame is applied continuously for ten minutes or until the actual flaming of the material being tested recedes from the point of maximum flame spread, which must not exceed 6 ft. (1.83 m) for Class A or 8 ft. (2.44 m) for Class B.

Burning Brand:

Burning Brand tests measure the roofing assembly's resistance to flame penetration caused by an ignited objectfalling on the roof. 3-1/3 ft. (1 m) wide by 4-1/3 ft. (1.32 m) long plywood test decks with the roof coverings in place are set up in the same manner as the intermittent flame test. Flaming grids of kiln-dried Douglas fir, 12 in. (0.31 m) x 12 in. (0.31 m) by 2-1/4 in. (0.6 m) weighing approximately 4-1/2 pounds (2.04 Kg) for Class A, and 6 in. x 6 in. by 2-1/4 in. (0.6 m) weighing approximately one pound for Class B, are placed on the roof covering, fanned by a 12 mph (19.3 km/h) wind and allowed to burn freely. The test is concluded when the brand is consumed and all evidence of flame, glow, and smoke has disappeared from both the exposed surface of the roof covering and the underside of the test deck or until failure occurs. The criterion for passing is the same as in the case of the intermittent flame exposure.

Burning Brand Test
Source:
 Wrimco Waterproofing






Wall Assembly Tests

  • Concept is to measure performance beyond spread of flame for each component
  • Unlike roof assembly, these tests are independent and cited in differing code sections
  • Various tests
    • NFPA 285, Evaluation of Flammability Characteristics of Exterior Non-Loadbearing Wall Assemblies Containing Combustible Components Using the Intermediate Scale, Multi-Story Test Apparatus
      • Vertical fire performance test
    • ASTM E119, Fire Tests of Building Construction and Materials
      • Rating is time-to-burn through
    • NFPA 268, Determining Ignitability of Exterior Wall Assemblies Using a Radiant Heat Energy Source




Interior Basic Test Requirements

  • IBC Section 2603 and IRC R316
  • Surface Burning Characteristics - ASTM E84
    • < 75 flame spread index
    • < 450 smoke developed index

  • Thermal Barrier Requirements
    • Typically 0.5 gypsum wall board

  • Elimination of thermal barrier under certain circumstances based on intermediate or large scale tests reflective of actual end use



Room Corner Tests

  • Concept is to assess larger-scale performance
  • 8-ft (or larger) walls & ceilings
  • Wood cribs or pallets soaked with fuel or lit by gas burner as flame source
  • Measures flame performance of foam plastic or finishes upon surfaces of foam plastic
    • Observations include heat flux, temperatures, heat/smoke release and rates, and time to flash-over
  • Standards include



Surface Burning Tests:

UL 723 (ASTM E 84): Test for surface burning characteristics of building materials

Steiner tunnel test according to the ASTM E 84
The tunnel test compares surface burning characteristics of tested materials to those of asbestos cement board and untreated red oak lumber. A rating of 0 is assigned to asbestos cement board and a rating of 100 is assigned to untreated red oak flooring. Flame spread ratings of various species of untreated lumber range from 60 to 230. During this test, smoke emissions are also measured and ratings are assigned on the same scale. These ratings are established during the first 10 minutes. However, unlike for fire retardant coatings, building codes require that the test be extended from 10 minutes to 30 minutes and the flame spread not progress more than 10 1/2 feet beyond the burners and show no evidence of progressive combustion. 

The determination of spread of flame forms the basis of classifying interiors finishes contained in all the building codes. It differs from code to code but now largely agree (see table below). 

Table 1: Flame-spread classification

Class according to
Uniform Building Code, section 204
Class according to
Life Safety Code, NFPA 101
Flame Spread
IA0-25
IIB26-75
IIIC76-200


ASTM E 162: Surface flammability of materials vs. radiant heat source
UL 790 (similar to ASTM E 108): Test methods for fire tests of roof coverings

Radiant panel test according to ASTM E 162
This test method is measuring surface flammability of materials employing a radiant heat source and an inclined specimen disposed such that ignition is forced near the upper edge. The flame front progresses downward. 

The ASTM E 162 was developed by the National Bureau of Standards in 1955. An almost identical method, ASTM D-3675, is used for cellular materials such as seat cushioning. This method measures flame spread and rate of energy release under a varying radiant flux from about 40 to 3 kW/m2. 

The key measurement is a flame spread index Is which is the product of the flame factor Fs and the heat Evolution factor Q:
Is = Fs x Q     (1)


The higher the index, the greater the flammability.