It's very important that propane tanks be stored upright and in a properly ventilated area.  Additional Storage Tips: Never store the Gas Growler or other propane containers in your living area or in a storage area that is directly attached to your living area. A shed or garage, provided it has adequate ventilation, is an ideal place for propane storage. It is also OK to store your Gas Growler outdoors in any covered location.  Propane containers should only be stored in vehicles with a vented storage locker; do not store the Gas Growler or other propane container in your trunk or sealed car.