33 C.F.R. § 165.5
(b) Any person may request that a safety zone, security zone, or regulated navigation area be established. Except as provided in paragraph (c) of this section, each request must be submitted in writing to either the Captain of the Port or District Commander having jurisdiction over the location as described in part 3 of this chapter, and include the following:
(c) Safety Zones and Security Zones. If, for good cause, the request for a safety zone or security zone is made less than 5 working days before the zone is to be established, the request may be made orally, but it must be followed by a written request within 24 hours.
(Requests for safety zones, security zones, and regulated navigation areas are approved by the Office of Management and Budget under control number 1625-0020)
[CGD 79-034, 47 FR 29660, July 8, 1982, as amended by CGD 79-026, 48 FR 35408, Aug. 4, 1983; USCG-2006-25150, 71 FR 39211, July 12, 2006; USCG-2020-0304, 85 FR 58281, Sept. 18, 2020]