ensure that, during that rehabilitation, not less than 1 carbon monoxide detector is installed per floor in the dwelling unit in accordance with standards and criteria acceptable to the Secretary for the protection of occupants in the dwelling unit. . (b) Supportive housing for persons with disabilities Section 811(j) of the Cranston-Gonzalez National Affordable Housing Act ( 42 U.S.C. 8013(j) ) is amended by adding at the end the following: (7) Carbon monoxide detectors (A) In general Each dwelling unit assisted under this section shall contain not less than 1 carbon monoxide detector installed per floor of the dwelling unit in accordance with standards and criteria acceptable to the Secretary for the protection of occupants in the dwelling unit. (B) Rehabilitation Each dwelling unit assisted under this section that is located in a property that is undergoing or planning a substantial rehabilitation project shall, during that rehabilitation, have installed not less than 1 carbon monoxide detector per floor of the dwelling unit in accordance with standards and criteria acceptable to the Secretary for the protection of occupants in the dwelling unit. . (c) Public and section 8 housing The United States Housing Act of 1937 ( 42 U.S.C. 1437 et seq.) is amended— (1) in section 3(a) ( 42 U.S.C. 1437a(a) ), by adding at the end the following: (8) Carbon monoxide detectors (A) In general Each public housing agency shall ensure, for each dwelling unit in public housing owned or operated by the public housing agency, that not less than 1 carbon monoxide detector is installed per floor in the dwelling unit in accordance with standards and criteria acceptable to the Secretary for the protection of occupants in the dwelling unit. (B) Rehabilitation With respect to public housing for which a public housing agency is undergoing or planning a substantial rehabilitation project, the public housing agency shall ensure that, during that rehabilitation, not less than 1 carbon monoxide detector is installed per floor in each