(a)
Current vehicles—
(1)
In general— Not later than 3 years after the date of enactment of this Act, any delivery vehicle owned or leased by the United States Postal Service as of that date shall be modified to include a climate control unit.
(2)
Annual report— The Postmaster General shall submit a progress report to Congress not later than 1 year after the date of enactment of this Act and annually thereafter until the modifications required under this subsection are complete.
(b)
Future vehicles— On or after the date of enactment of this Act, the Postmaster General may not purchase or lease any delivery vehicle for use by the United States Postal Service unless that vehicle has a climate control unit.