Section 1090.1405 - National fuels survey program(a)Program participation.(1) A gasoline manufacturer that elects to account for oxygenate added downstream under § 1090.710 must participate in the national fuels survey program (NFSP) specified in this paragraph (b) of this section.(2) A party required to participate in an E15 survey under § 1090.1420(a) must participate in the NFSP specified in paragraph (b) of this section or a survey program approved by EPA under § 1090.1420(b) or (c) .(3) Other parties may elect to participate in the NFSP for purposes of establishing an affirmative defense against violations of requirements and provisions under this part as specified in § 1090.1720 .(b)Program requirements. The NFSP must meet all the following requirements: (1) The survey program must be planned and conducted by an independent surveyor that meets the independence requirements in § 1090.55 and the requirements specified in § 1090.1410 .(2) The survey program must be conducted by collecting samples representative of gasoline and diesel retail outlets in the United States as specified in § 1090.1415 .