3109.5.1.1 Openings.
BC § 3109.5.1.1
Openings in the barrier shall not allow passage of a 4-inch-diameter (102 mm) sphere.
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What is NYC BC § 3109.5.1.1?
Quick Answer
This section establishes that openings in barriers must be designed to prevent the passage of a sphere with a diameter of 4 inches (102 mm). The rule is enforced by the Department of Buildings. Applies to building owners responsible for barrier compliance.
General informational summary. Not legal advice for your situation. Consult an attorney before acting on any specific matter.
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