Overhang: The extraction Cover need to overhang the cooking products by no less than 250mm for the front and sides. For combi-steamers or baking ovens, this increases to 600mm. Besides your kitchen extraction system, you may well be also be required to install an automatic fireplace suppression system and, here https://commercial-kitchen-extrac13688.goabroadblog.com/35863682/commercial-kitchen-extract-systems-fundamentals-explained