How Often Should Your Kitchen Exhaust Hood & System Be Cleaned?

Fire Prevention/Protection, Kitchen Exhaust Hood Cleaning

How frequent should we clean our kitchen exhaust hood system, may be the the #1 question we receive!

Why You Need to Clean Your Kitchen Hood

Your kitchen hood is an important tool not just for directing what comes off of the cooking equipment or the comfort of your staff. The kitchen hood is designed with life safety in mind. These systems (filters, hood, duct & fan) remove fumes, smoke, and grease-laden vapors to keep the air fresh while protecting you and your team against fire hazards. It is imperative to do regular hood cleaning to keep the system working properly. Hoods accumulate grease residue over time. Depending on what kind of food the restaurant serves, types and amounts of oils, and volume of business, will determine the rate and thickness of grease buildup. If the kitchen exhaust system is not cleaned regularly, the buildup can cause the exhaust system to work poorly. Kitchen Exhaust Systems with grease build-up, not only is a fire hazard, it affects the air quality of the workplace, as well as that of the food served. 

Keeping Your Restaurant Up to Code

Because kitchen hoods and exhaust systems are within the category of “fire and life safety” there is code that regulates how often they should be cleaned. So if you have a restaurant or commercial kitchen, there are strict codes that must be followed to remain compliant. Insurance companies, fire marshals, building inspectors, and health inspectors all require regular kitchen hood cleanings. Not only will you stay up to code with regular cleaning, it may also qualify your business for insurance rate reductions. Failure to comply could leave your livelihood at risk should a fire occur.

How Often You Need to Clean Your Kitchen Hood 

The general rule of thumb for kitchen hood cleaning is every three months but this depends on several factors our experts can help you access. Some commercial/restaurant exhaust systems that use wood or charcoal-burning stoves need to be inspected/cleaned monthly. The frequency of service is based on several factors such as the volume of business, types of food being cooked, and types of cooking equipment.
 
The National Fire Protection Association suggests along with Averus the following frequencies:
  • Wood-burning or charcoal-burning                           MONTHLY TO WEEKLY 
  • 24-hour restaurants / High Volume                           QUARTERLY to SIX TIMES PER YEAR
  • Hamburger and fast-food restaurants                      QUARTERLY to SIX TIMES PER YEAR
  • Char Broiler / Wok                                                            QUARTERLY to SIX TIMES PER YEAR     
  • Hoods over non-grease-creating appliances          ANNUALLY to SEMIANNUAL
  • Steam kettles, dishwashers, or soup vats                ANNUALLY to SEMIANNUAL                     
  • Churches, day camps, senior centers                       ANNUALLY
Aside from Table 11.4 Schedule of Inspection for Grease Buildup, NFPA 96 also quantifies the amount of grease build-up based on the thickness. The amount of build-up triggers the need for cleaning. How much grease does it take before it’s time to have your system serviced? Below, is the maximum amount of grease build-up allowed. 
 
NFPA 96 (2017ed.)
 
11.6.1.1.3 Where a measured depth of 2000µm (.078 in.) is observed, the surfaces shall be cleaned in accordance with 11.6.1. How thick is .078 inch? This is approximately the thickness of a nickel. 
 
11.6.1.1.4 Where a measured depth of 3175µm (0.125 in.) is observed in a fan housing, the surfaces shall be cleaned in accordance with 11.6.1. How thick is .125 inch? This is approximately the thickness of two stacked pennies.