Verify fire-rated duct wrap/enclosure listing scope for a grease duct penetrating a fire-rated floor or ceiling

Steps

1. Confirm the wrap or enclosure product has been tested and listed as a grease duct enclosure system per ASTM E2336 (Standard Test Methods for Fire Resistive Grease Duct Enclosure Systems), not merely a general-purpose fire wrap or air-duct insulation product
2. Check the specific listing details (number of layers, wrap thickness, overlap/seam method, fastening) against the manufacturer's listed installation instructions — ASTM E2336 is a test method, and compliance depends on the actual tested/listed assembly, not the standard name alone
3. Confirm the achieved fire-resistance rating (commonly 1-hour or 2-hour enclosure systems are offered) matches what the fire-rated floor/ceiling assembly requires at that penetration
4. Verify the enclosure is sealed around the duct at the point of penetration of the rated assembly, and extends continuously from the lowest rated ceiling/floor above the hood through the roof, per NFPA 96's continuous-enclosure requirements
5. Where a wrap system is used as an alternative to a traditional fire-rated shaft, confirm the AHJ accepts this approach and that clearance requirements from the duct/fan to the enclosure's interior surface are met for the applicable combustible/noncombustible construction