Is it really necessary to hang a hood above a gas conveyor oven? So yes why?

Thanks for answering my question.


i’d check you local health dept… but as far as here, no, you don’t need one. But I would suggust some type of exhaust fan because usually it will get pretty freakin hot in that kitchen.

I’m not sure if one is required for you, but the mere fact that you are burning gas, you should probably have one. Also, I am much in agreement with Integraoligist, it will drastically help with the heat in the kitchen.

Ditto. In our county of Illinois anyway, the health department doesn’t require one. But as it was put to me, realize that appliance is going to be chugging all day long at 500 degrees or so. Where you you think that heat is going? When we get ready for build-out we’ll be installing a hood just to try to keep the kitchen a tad more comfortable if nothing else.

What about Class I vs. Class II?

We’re building out a new store, and the building department is saying we need to install a Class I (fire suppression) hood over the conveyor pizza ovens. I’ve never seen fire suppression over a conveyor oven before. The inspector says it has always been in the building code - it’s just never been inforced.

I don’t have any experience with this as I have deck ovens in my current store, and they have a direct flue.

are you going to be doing anything that will produce grease? if not, which if all you are doing is pizza, then you shouldnt have grease, and should have them write down the code and prove it to you.

We have 2 stores that have class I hoods with suppression, and the inspectors have told us that its great that we have them, but they arent necessary. All of the other stores that I know of have class II hoods, which in kansas, is all you really need since you’re just blowing hot air around.

From what i have been told by my owner, Once you get to the point where you have grease, either from uncooked meat(sometimes) or in a fryer, then you have to go to the class I hood.

There is only 1 answer to this question that matters…That is the one given to you by your local building inspector…

The building code requires a hood over a pizza oven or even a dish washer. The national fire protection code requires an all welded hood. The NSF code will, no doubt, call for the hood to be made of stainless steel. The local Fire Marshall may or may not require a fire protection system.

The hood removes any grease vapors from cooking, removes heat and humidity, and very important removes carbon monoxide plus any unburned gas from the building. Being exposed to carbon monoxide and un burned gas for an extended period can make you very ill. Being exposed to a large amount can kill you.

Older conveyor ovens burn only about 80 % of the gas so a substantial amount of unburned gas remains.
Deck ovens also do not burn all the gas.

Pizza shops operating without a hood run the risk of the owner and staff developing carbon monoxide poisoning. This can be a very sneaky malady and the victim can be diagnosed with many other problems and be incorrectly treated for years and never become better.

Note that the hood when installed will require a system to replace into the building any air removed by the exhaust system. Better known as, make up air. Not doing the combination of hood and make up air supply properly can cost you a lot to operate over the years and also if not properly done can make the kitchen very uncomfortable.

I will be happy, at no charge, to consult with any of you on your ventilation system.

George Mills

Piper, especially if you are using pre-cooked toppings you can make the argument that you are merely re-heating rather than cooking. The difference…grease. If there’s no grease, essentially you baking a pizza is no difference than me going to my house and baking a frozen pizza, or take n bake pie.

This is your best argument around needing a class I hood with fire suppression. Our architect made this argument and we were able to not have the fire suppression. It ultimately is going to come down to your building inspector.

wait a minute you are running a 500 degree oven, pushing through how many cubic feet of gas an hour?? and you are cool to not have fire suppression?? i don’t think i would work in any kitchen that didn’t have fire protection. did you do this just to save a buck?? does your insurance company know this?? im sorry but to me this seems downright unsafe and irrisponsible. how big of a insurance policy do you have on the store??


Has nothing to do with the gas as it is nearly completely combusted. You need fire suppression if you have grease vapors. A Class II hood is suffficient for impingement ovens according to the national fire code.

Charles is correct as to the code requirements.

The kicker is that any Building Department or Health Department can enforce more stringent regulations, and the Fire Marshall can require fire protection.

We have been trying to help operators throughout the nation resist the implementation of the more stringent requirements. Unfortunately we have enjoyed little success. The local authorities most always get their way.

George Mills