N.Y.C. Admin. Code § BC 2403: Section BC 2403: General Requirements for Glass

2403.1 Identification.

Each pane shall bear the manufacturer's label designating the type and thickness of the glass or glazing material. The identification shall not be omitted unless approved and an affidavit is furnished by the glazing contractor certifying that each lite is glazed in accordance with approved construction documents that comply with the provisions of this chapter. Safety glazing shall be identified in accordance with Section 2406.3.

Each pane of tempered glass shall be permanently identified by the manufacturer. The identification label shall be acid etched, sand blasted, ceramic fired, laser etched, embossed or of a type that, once applied, cannot be removed without being destroyed.

Exception: Tempered spandrel glass shall be permanently labeled unless doing so would weaken, alter the performance of, or cause breakage of the spandrel glass, as determined by the manufacturer. Where the manufacturer makes such a determination, the tempered spandrel glass shall be provided with a removable paper marking by the manufacturer, and an affidavit shall be provided in accordance with this section.

2403.2 Glass supports.

Where one or more sides of any pane of glass are not firmly supported, or are subjected to unusual load conditions, or as requested by the applicant, detailed construction documents, detailed shop drawings and analysis or test data ensuring safe performance for the specific installation shall be prepared by a registered design professional.

2403.3 Framing.

To be considered firmly supported, the framing members for each individual pane of glass shall be designed so the deflection of the edge of the glass perpendicular to the glass pane shall not exceed 1/175 of the glass edge length or 3/4 inch (19.1 mm), whichever is less, when subjected to the larger of the positive or negative load where loads are combined as specified in Section 1605. Gaskets, washers, shims, seals or spacers shall be used where required to prevent contact of glass to metal components in framing and supports. The system shall allow for movement.

2403.4 Interior glazed areas.

Where interior glazing is installed adjacent to a walking surface, the differential deflection of two adjacent unsupported edges shall not be greater than the thickness of the panels when a force of 50 pounds per linear foot (plf) (730 N/m) is applied horizontally to one panel at any point up to 42 inches (1067 mm) above the walking surface.

2403.5 Louvered windows or jalousies.

Float, wired and patterned glass in louvered windows and jalousies shall be no thinner than nominal 3/16 inch (4.8 mm) and no longer than 48 inches (1219 mm). Exposed glass edges shall be smooth.

Wired glass with wire exposed on longitudinal edges shall not be used in louvered windows or jalousies.

Where other glass types are used, the design shall be submitted to the department for approval.