D.C. Code § 8-415
The Mayor may waive all or part of any applicator certification examination required by this chapter and issue a license to a nonresident of the District of Columbia who is certified by a state under a certification plan that has been approved by the Administrator and which is substantially in accordance with the provisions of this chapter; provided, that such state has a reciprocity provision granting similar accommodation to applicators certified by the District of Columbia. Certifications issued pursuant to this section may be suspended or revoked in the same manner and on the same grounds as other certifications issued pursuant to this chapter, or upon suspension or revocation of the applicator's certification by the state, issuing the applicator's original certification.
D.C. Code § 8-415