Why is monthly cleaning needed for cooking installations using solid fuel?

January 11, 2022

by Nils Deacon, Manager, Inspections and Rating Services

There are a variety of cooking venues that use solid fuel. These include barbeque pits using charcoal, wood fired pizza ovens, and broilers using briquettes.

Solid fuel cooking produces grease laden vapors and other by-products of combustion. Smoke, unburned wood, and water vapor rise up into the hood and duct. As they condense, creosote is formed. Combined with grease laden vapors, grease infused creosote is produced. The creosote has a much lower flash point and auto ignition temperature than the grease laden vapors that traditional gas and electric cooking produces. Increased mitigation measures are necessary.

NFPA 96, The Standard for Ventilation Control and Fire Protection of Commercial Cooking Operations addresses this hazard by requiring at least a monthly cleaning of the equipment, including the hood and duct if present.

The combustion chamber itself must be cleaned down to its original surface once each week.

DISCLAIMER: This information reflects the interpretation of MSO, Inc. with regard to NFPA Standards and Codes. It does not represent NFPA’s official position on the items discussed.


Grease and creosote in hood and filters.