Except in the case of tax-paid deliveries into the fuel supply tanks of motor vehicles, it shall be unlawful to make bulk sales of LP-gas to any person who: (a) Is not licensed as a dealer or user of LP-gas; (b) is not the holder of a valid special LP-gas user permit; or (c) who has not first furnished the seller a signed statement that such gas is purchased exclusively for nonhighway use or for use by municipally owned vehicles used primarily for law enforcement purposes and none of the LP-gas purchased or acquired in Kansas on which the Kansas tax has not been paid by the purchaser will be delivered by the purchaser into the fuel supply tanks of motor vehicles. Except as otherwise prescribed by rules and regulations of the secretary of revenue, such statement, when furnished to a licensed dealer, shall be effective as long as the licensed dealer continues to sell and deliver LP-gas to the purchaser, unless the statement is revoked in writing by the purchaser, dealer or director, or unless the dealer has knowledge that some of such fuel is used in a manner contrary to the signed statement. The provisions of this act shall not apply to deliveries made into storage facilities that do not have hoses and transfer equipment capable of filling the supply tank or tanks of a motor vehicle.