Del. Code Ann. tit. 16, § 6405
The documents required by § 6404(3) of this title must be filed with the Fire Marshal before June of each year, but if the amusement ride is inspected under § 6404(1) of this title more than once a year, the inspection certificate must be filed not later than 15 days after each inspection and the insurance policy must be filed before June of each year.