Model building codes

Because the ASHRAE/IES standard contained both mandatory requirements and recommendations, it was difficult to adopt and implement as a uniform building code. Such codes must clearly state minimum requirements that can be uniformly interpreted and applied. For this reason it was determined that a model code was needed that contained only the... 

It is clear that the ultimate solution rests with the ISO tests used as a part of a European Classification System adopted as a part of a common or model building code for the European Community. 

As mentioned earlier, the fire hazard of interior finish materials is primarily due to the potential for rapid wind-aided flame spread over the surface. It is therefore not a surprise that reaction-to-fire requirements for interior finish materials in U.S. building codes are primarily based on performance in a wind-aided flame spread test. The apparatus of this test is often referred to as the Steiner tunnel. The Steiner tunnel test is described in ASTM E 84. Although the test does not measure any material properties that can be used in a model-based hazard assessment, a discussion of the test is included here due to its practical importance for the passive fire protection of buildings in the United States. 

The classification of linings in the U.S. model building codes is based on the FSI and SDI (smoke developed index). The latter is based on the area under the light transmission versus time curve normalized to the area for red oak flooring, which by definition has an SDI of 100. There are three classes Class A for products with FSI < 25, Class B for products with 25 < FSI < 75, and Class C for products with 75 < FSI < 200. In all cases, the SDI must be 450 or less. Class A products are generally permitted in enclosed vertical exits. Class B products can be used in exit access corridors and Class C products are allowed in other rooms and areas. 

Several standard room/corner test protocols are now available and are specified in codes and regulations for qualifying interior finishes. For example, U.S. model building codes require that textile wall coverings for use in unsprinklered compartments meet specific performance requirements when tested according to NFPA 265. The principal requirement of these tests is that flash-over does not occur. The same codes also require that all other interior wall and ceiling finish materials comply with requirements based on NFPA 286, including a limit on the total smoke released. 

Fire performance of foam parts is regulated in national or industry standards such as DIN 4102 and ASTM E84 via the model building codes in the USA. 

ASTM E 84 Steiner Tunnel Test. This test, which uses very large samples (20 ft x 20 1/4 in.) is referenced in all model building codes for evaluating flame spread and smoke emission of foam plastic insulation. The test apparatus consists of a chamber or tunnel 25 ft. long and 17 3/4 X 17 5/8 in. in cross section, one end of which contains two gas burners. The test specimen is exposed to the gas flame for ten minutes, while the maximum extent of the flame spread and the temperature down the tunnel are observed through windows. Smoke evolution can also be measured by use of a photoelectric cell. The flame spread and smoke evolution are reported in an arbitrary scale for which asbestos and red oak have values of 0 and 100, respectively. More highly fire-retardant materials have ratings of 0-25 by this method. 

With all these complex interactions, it is desirable to build a model that can quantitatively evaluate all the components of the system. Rittmann and VanBriesen (1996) and VanBriesen and Rittmann (1999) developed the code ccbatch to do just that, ccbatch, which stands for "co-contaminant batch reactor", has three components. 

Stage 5 (Building the Model). This involves the classical steps of defining the conceptual model, selecting model code, calibrating the model against field data and... 

The International Code Council (ICC) is a joint venture of the three major code councils in the U.S., established to develop uniform national model building codes. The existing ICC model codes do not include hydrogen as an energy source or fuel cells as either power-generating devices or as appliances. To address this limitation, the ICC has established an Ad-Hoc Committee (HAHC) on hydrogen... 

DOE O 420.1, Chg 3 4.2.7 Facility Safety. All new construction shall, as a minimum, conform to the Model Building Codes applicable for the state or region, supplemented with additional safety requirements associated with the facility hazards. Inventories of chemicals must be tracked in order to ensure that chemical limits specified in applicable regulations are not exceeded. 

The EPA issued Model Standards and Techniques for the Control of Radon in New Residential Buildings in 1994. The publication was intended to serve as a model for jurisdictions developing building codes or standards apphcable to their radon control requirements, primarily for one- and two-family homes and other residential buildings of three stories or less. There is no requirement in the Act that new homes meet any specific radon level or that private home owners must test their homes. Consistent with its limited authority under the Act, the EPA was careful to point out in several sections that the Model Standards were not intended to supersede radon resistant... 

Stress analysis is the determination of the relationship between external forces applied to a vessel and the corresponding stress. The emphasis of this book is not how to do stress analysis in particular, but rather how to analyze vessels and their component parts in an effort to arrive at an economical and safe design—the difference being that we analyze stresses where necessary to determine thickness of material and sizes of members. We are not so concerned with building mathematical models as with providing a step-by-step approach to the design of ASME Code vessels. It is not necessary to find every stress but rather to know the... 

The two-phase motion problem is very stiff, with a wide separation of timescales and a transport matrix which becomes singular as the solution relaxes to its quasi-steady state. The asymptotic analysis presented eliminates the stiffness that is the bane of numerical simulations, affording computational speed-up of 3-4 orders of magnitude over the full system. Building this model into a unit cell simulation code promises huge reductions in computational cost and admits the possibility of performing either full stack-based calculations or doing extensive inverse calculations and parameter estimation. 

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