5.1 Use of this guide can be beneficial in determining the relative effectiveness of building systems as it relates to potential protection from passage of products of combustion between building spaces under both ambient and elevated temperatures.

5.2 Determining the relative effectiveness of a building system to limit the total air leakage between building spaces is important in the evaluation and selection of potential construction components to meet desired performance requirements for a building.

5.3 To properly assess the relative effectiveness of a building system’s total air leakage rate, a guide as to how to aggregate the individual component air leakage rates into a total air leakage rate for the building system is needed.

5.4 It is the intent of this guide to provide a methodology for the conversion of individual component air leakage rates into common values that can be aggregated into a total air leakage rate for a building system, thus providing a means for establishing the relative effectiveness of various building systems to resist the passage of products of combustion.

1.1 This guide provides a method of evaluating the relative effectiveness of building systems to resist the passage of smoke.

1.2 The method of evaluating the relative effectiveness of a building system is based on the aggregation of leakage rates of openings, penetrations, joints, and interfaces of the construction elements forming the building system.

1.3 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.