It is important to keep the kitchen in your restaurant clean if you want the business staying healthy. Under this, periodic kitchen exhaust cleaning is the most vital activity to ensuring you maintain a clean kitchen.
The restaurant hood is where you should start. You have the restaurant hood for two things: protecting the kitchen from fire by getting rid of the grease; and getting the smoke out so the kitchen staff can cook without suffocating.
The exhaust works by pulling the greasy smoke into the hood on top of the cooking area, after which it proceeds to the filters at the back of the exhaust. There, it is turned back to grease, which is then dumped into a catch tray.
There are three basic designs restaurant hood use. These are the canopy, the galley, and the downdraft. The efficiency of the hood is decided by how close it is to the cooking surface. It is the place where the first filtration of the smoke happens. The size of this is usually decided based on how big the cooking equipment is.
Most restaurants use one of two types of commercial hoods. Type 1 is generally situated over where the grease producing equipment is used. It has legally required that these hoods be continuously welded, and suspended using non-combustible hangers.
Then there is Type 2, which is used over kitchen appliance that only gives out steam, fumes and odors. Cleaning these hoods is not as big a part of kitchen exhaust cleaning, as with Type 1. Type 2 hoods should not be placed above grease producing equipment, and if this is found to be the case, the kitchen cleaning service is responsible for informing you that this is a fire hazard.
Where kitchen exhaust cleaning is concerned, if there are dampers in the throat of the hood, there should be a proper access for the cleaners. NFPA #96 says this access should be no farther than 18 inches from the hood.
You do not see many downdraft hoods these days, but they are still in use. Before the smoke is let out of the building, it is diverted under it using air currents. During kitchen exhaust cleaning, this poses a hazard because of the heavy amount of grease that accumulates under gravity.
Canopy style hoods are more common now, because of the simple design and easy maintenance. Here, you need to make sure the service is cleaning the exhaust system as a whole, and not just the hood.