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NYC Building Code

§ 427.7.4 — § 427.7.4

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What is NYC BC § 427.7.4?

Quick Answer

This section regulates the maximum allowable quantity of unstable (reactive) materials in laboratory units, stipulating limits based on fire-rated construction. It specifies that up to 6 pounds of such materials are permitted, with exceptions for units meeting certain fire safety standards. Applies to laboratory operators managing hazardous materials.

General informational summary. Not legal advice for your situation. Consult an attorney before acting on any specific matter.

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427.7.4 Unstable (reactive).

BC § 427.7.4

The total quantity of unstable (reactive) material allowed within a laboratory unit, excluding any quantities in a storage room, shall not exceed 6 pounds (2.7 kg), provided not more than 1 pound (0.454 kg) of which is Class 3 unstable (reactive). Exception: The total quantity of unstable (reactive) material allowed within a laboratory unit that is provided with walls, floors and ceilings that separate the laboratory unit from all adjoining areas by 2-hour fire-rated construction shall not exceed 12 pounds (5.4 kg), provided not more than 1 pound (0.454 kg) of which is Class 3 unstable (reactive).

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