Del. Code tit. 16 § 7307
Approved portable oil-fueled heaters may be offered for sale, sold and used in structures in this State; however, the use of a portable oil-fueled heater in multi-unit residential buildings is specifically prohibited. Any portable oil-fueled heaters which are not approved may not be offered for sale, sold or used in structures in this State. Any portable oil-fueled heater may be offered for sale, sold and used in locations other than structures unless specifically prohibited by legislation of this State. Any listed portable oil-fueled heater shall be approved if it satisfies the requirements hereinafter set forth and if the supplier has certified to the State Fire Prevention Commission that it is listed and in compliance herewith.
16 Del. C. § 7307