A person who is in the water using an underwater breathing device may display a diver's flag constructed of rigidly supported material at least 12 inches by 12 inches in area of red background with a white diagonal stripe. This diver's flag may be displayed on a boat or surface float and must extend a minimum distance of three feet from the surface of the water. The diver's flag shall be placed at or near the point of submergence and constitutes a warning that a diver is submerged and may be within 100 feet of the flag. A diver shall remain within 100 feet of the diver's flag while at or near the surface. A boat operator within sight of a diver's flag shall proceed with caution, steering clear of the flag by a distance of 100 feet. Outside commercial shipping lanes, boats maneuvering within a 100-foot radius of a diver's flag shall be slowed to no-wake speeds or five miles per hour, whichever is necessary to maintain steerage in the seaway. A diver's flag shall be displayed only while diving operations are underway.