D.C. Mun. Regs. tit. 6, r. 6-B1206
Pursuant to section 701(b) through (f) of the CMPA (D.C. Official Code § 1-607.01(b) through (f)) (2006), and notwithstanding the provisions of section 1203.1 of this chapter, and to the extent that a variation in a work schedule does not result in a substantial disruption of District government business, an employee whose personal religious beliefs require that he or she abstain from working at certain times of the workday or workweek shall be entitled to reasonable accommodation for the free exercise of religion.
The accommodation to be provided may include an adjustment in the work schedule when the employee elects to make up the time off rather than to charge the time off to leave.
If the need to take the time off for religious reasons is foreseeable, the employee shall request an adjustment of his or her work schedule as provided in section 1206.2 of this section and obtain supervisory approval of the adjustment at least ten (10) days before taking time off from work.
A request to adjust the employee's work schedule may be disapproved if it is demonstrated that the adjustment would clearly interfere with the efficient conduct of the activities of the employing agency.
Nothing in this section shall be construed to totally exempt an employee from being required to work rotating shifts including working on weekends as a result of religious preferences.
Nothing in this section shall be construed to limit the use of other forms of leave authorized by this chapter.
Each personnel authority shall provide written notice to an employee, at the time that the employee accepts employment that he or she may receive the religious accommodation described in section 1206.1 of this section.
D.C. Mun. Regs. tit. 6, r. 6-B1206