Do all commercial cooking installations require hood-duct and automatic extinguishing system protection?
An underwriter recently asked if a certain cooking installation needed a complete hood-duct and automatic extinguishing system. The appliances in question were a countertop grill and a two-burner countertop range. Both were electric powered. The listing agent thought this power source made a difference in the level of protection required.
NFPA 96, the Standard for Ventilation Control and Fire Protection of Commercial Cooking Operations provides guidance for this question. Natural gas or propane fueled appliances require this protection because of the nature of the fuel, which releases products of combustion when used, and most importantly, grease-laden vapors. Most electric powered equipment that produces grease-laden vapors is also required to be fully protected. However, the standard does not require electric appliances that are listed under UL 197 – Commercial Electric Cooking Appliances to be vented with a hood and duct system. This is because they are designed to produce very small amounts of grease emissions. They must be specifically listed and tested under UL 197. Most electric cooking equipment found in commercial kitchens does not have this listing.
Other electric equipment not needing a hood-exhaust system are recirculating systems which include a cooking appliance, collection hood, grease filters, and a fire suppression system.
Are different types of hoods needed in commercial cooking operations?
Commercial cooking equipment that produces various types of exhaust must be protected with a hood. There are two types of hoods – Type I and Type II. Type I hoods are designed to capture and hold grease and smoke emissions from cooking equipment. These hoods are designed for use over equipment such as griddles, fryers, broilers, ovens, ranges, and wok ranges. UL-NFPA Type II hoods are designed to remove steam or heat and are used over equipment such as ovens, steamers, kettles, and pasta cookers. UL-NFPA Type I hoods must be secured with non-combustible supports and should be designed for thorough cleaning of grease and creosote if applicable. They should also be equipped with grease extractors or filters that are fitted and easily removeable to be cleaned. Clearances to combustible walls and ceilings must be 18’’ unless the hood is rated for reduced clearances. Type II hoods do not require these clearances because of the low temperature exhaust handled.
DISCLAIMER: This information reflects the interpretation of MSO, Inc. with regard to NFPA Standards and Codes and other code sources. It does not represent these codes’ official position on the items discussed.
This article was published in UNDERWRITERS' CORNER and is provided courtesy of MSO®, Inc. (The Mutual Service Office, Inc.) by Nils Deacon, Manager, Inspections and Rating Services. MSO provides custom rate, form and statistical services for all property and casualty insurance lines except workers compensation. This includes customized forms and manuals for insurers, MGA's and agents/brokers. MSO's goal is to provide a simpler, more profitable way to underwrite risks. Additional information is available at www.msonet.com. E-mail to squimby@msonet.com.