Ooni pizza ovens are meant for outdoor use only, so normally you wouldn't want to use it in your garage. On the other hand, if you're using your Ooni pizza oven right next to a wide open garage door there shouldn't be any problems as long as it's 3 feet (1 meter) from any walls. Wherever you use you Ooni pizza oven, never leave it unattended and don't let children or pets near it while in use.