; and (2) any testing of employees of the eligible taxpayer or guests of such trade or business or such property for symptoms of COVID–19. For purposes of the preceding sentence, a trade or business shall be treated as having reduced services if such trade or business reduced hours of operation, number of employees or employee hours, or capacity of seating areas, closed seating areas, or took any other measures which reduced services provided or operations of the trade or business as determined by the Secretary of the Treasury. (d) Denial of double benefit No deduction shall be allowed under any provision of chapter 1 of the Internal Revenue Code of 1986 with respect to any amount taken in account in determining the credit allowed to a taxpayer under this section. (e) Regulations and guidance The Secretary of the Treasury (or the Secretary's delegate) may prescribe such regulations and other guidance as may be appropriate or necessary to carry out the purposes of this section. (f) Termination This section shall not apply to any costs paid or incurred in taxable years beginning after December 31, 2022. 6. Credit for travel expenditures (a) In general Subpart C of part IV of subchapter A of chapter 1 of the Internal Revenue Code of 1986 is amended by inserting after section 36 the following new section: 36A. Credit for travel expenditures (a) Allowance of credit In the case of an individual who pays or incurs any qualified travel expenses during a taxable year, there shall be allowed as a credit against the tax imposed by this subtitle for such taxable year an amount equal to 50 percent of such expenses. (b) Limitations (1) Dollar limitation The credit allowed under subsection (a) for any taxable year shall not exceed the sum of— (A) $1,500 ($750 in the case of a married individual filing a separate return), plus (B) $500 for each qualifying child (as defined in section 152(c)) of the individual, but not to exceed $1,500. (2) Limitation based on adjusted gross income (A) In general The amount allowable as a credit