5.1 This practice is used to determine the LR of specified glass types and constructions exposed to uniform lateral loads.
5.2 Use of this practice assumes:
5.2.1 The glass is free of edge damage and is properly glazed,
5.2.2 The glass has not been subjected to abuse,
5.2.3 The surface condition of the glass is typical of glass that has been in service for several years, and is weaker than freshly manufactured glass due to minor abrasions on exposed surfaces,
5.2.4 The glass edge support system is sufficiently stiff to limit the lateral deflections of the supported glass edges to no more than 1/175 of their lengths. The specified design load shall be used for this calculation.
5.2.5 The deflection of glass or support system, or both, shall not result in loss of glass edge support.
Note 1: Glass deflections are to be reviewed. This practice does not address aesthetic issues caused by glass deflection.
Note 2: This practice does not consider the effects of deflection on insulating glass unit seal performance.
5.3 Many other factors shall be considered in glass type and thickness selection. These factors include but are not limited to: thermal stresses, spontaneous breakage of tempered glass, the effects of windborne debris, excessive deflections, behavior of glass fragments after breakage, blast, seismic effects, building movement, heat flow, edge bite, noise abatement, and potential post-breakage consequences. In addition, considerations set forth in building codes along with criteria presented in safety-glazing standards and site-specific concerns may control the ultimate glass type and thickness selection.
5.4 For situations not specifically addressed in this standard, the design professional shall use engineering analysis and judgment to determine the LR of glass in buildings.
1.1 This practice describes procedures to determine the load resistance (LR) of specified glass types, including combinations of glass types used in a sealed insulating glass (IG) unit, exposed to a uniform lateral load of short or long duration, for a specified probability of breakage.
1.2 This practice applies to vertical and sloped glazing in buildings for which the specified design loads consist of wind load, snow load and self-weight with a total combined magnitude less than or equal to 15 kPa (315 psf). This practice shall not apply to other applications including, but not limited to, balustrades, glass floor panels, aquariums, structural glass members, and glass shelves.