FYI Here are the statutes, and yes the 21" was a typo.
§63-4201.
In addition to the terms defined by the Oklahoma Vessel and Motor
Registration Act, Section 4002 et seq. of this title, for the purposes
of the Oklahoma Boating Safety Regulation Act, Section 4201 et seq. of
this title:
1. "Anchorage area" means a place specifically indicated by the
authority in charge of a body of water for anchoring or mooring a
vessel;
2. "Buoy" means an anchored marker for marking a position on the
water, or a hazard, shoal or mooring, or any other prohibitive
activity area;
3. "Capacity plate" means a sign posted in view of the operator's
station on a vessel which designates the maximum weight capacity and
horsepower restrictions of a vessel for safe operation;
4. "Class A vessel" means a vessel which is less than sixteen (16)
feet in length;
5. "Class 1 vessel" means a vessel which is sixteen (16) feet or
longer and less than twenty-six (26) feet in length;
6. "Class 2 vessel" means a vessel which is twenty-six (26) feet or
longer and less than forty (40) feet in length;
7. "Class 3 vessel" means a vessel which is forty (40) feet or longer
in length;
8. "Diver's flag" means a red flag not less than twenty (20) inches by
twenty-four (24) inches with a four-inch white stripe running from one
upper corner to a diagonal lower corner, and such flag is used to
indicate a submerged diver;
9. "Emergency vessel" means any law enforcement vessel which is
legally authorized to operate in the emergency mode;
10. "Law enforcement vessel" means any vessel legally authorized to
operate under the color of law;
11. "Manipulate" means to guide, steer or otherwise control;
12. "Marine sewage" means any substance, treated or untreated, that
contains any of the waste products of humans or animals or foodstuffs;
13. "Marine toilet" means any latrine, head, lavatory or toilet
intended to receive marine sewage and which is located on or in any
vessel;
14. "Operator" means the person who operates, has actual physical
control, or has charge of the navigation or use of a vessel;
15. "Parasail" means any device which, when airborne, is used or
capable of being used for lifting or suspending a person who is being
or will be towed by a vessel;
16. "Personal flotation device" means only a United States Coast Guard
approved flotation device;
17. "Personal watercraft" means a vessel which uses an inboard motor
powering a water jet pump as its primary source of motive power and
which is designed to be operated by a person sitting, standing or
kneeling on the vessel, rather than the conventional manner of sitting
or standing inside the vessel, or a vessel which is similar in
appearance and operation to a personal watercraft but which is powered
by an outboard or propeller driven motor, or a vessel less than
sixteen (16) feet in length which travels across the water above or on
a cushion of air provided by engines, propellers or other means of
propulsion;
18. "Reportable boating accident" means an accident, collision or
other casualty involving a vessel which results in loss of life,
injury sufficient to require first aid or medical attention or actual
physical damage to property in excess of Five Hundred Dollars
($500.00);
19. "Sanctioned event" means any organized event on the waters of this
state, including but not limited to regattas, motorboat or other boat
races, marine parades, tournaments and exhibitions, which is approved
and permitted by an authorizing agency;
20. "Under way" means the movement of a vessel whether by mechanical
or nonmechanical means which is other than incidental to the force of
wind, waves or current; and
21. "Wake" means the track of waves left by a vessel or other object
moving through the water, and such waves are greater than the natural
waves in the immediate area of the vessel, or are cresting and showing
white water, or may cause injury or damage to any person or property.
§63-4211.
A. Any person diving or submerging in a body of water with the aid of
any mechanical diving or breathing device or suit shall place a buoy
with a flag in the water at or near the point of submergence or fly a
flag from a vessel indicating divers are present, in the following
manner:
1. Either the nationally recognized diver's flag or Alpha flag may be
flown;
2. When flown from a vessel, at least one flag shall be flown not less
than one (1) meter above the highest point of the vessel and shall be
visible from a three-hundred-sixty-degree circle;
3. The buoy, flag or flags shall be in place only while actual diving
operations are in progress;
4. No diving buoys may be closer than one hundred (100) yards to any
functional boat ramp; and
5. The flag or flags shall be in good condition and legible, and the
flag shall be in the extended position so as to be visible to any
other vessel.
B. It shall be unlawful for any person to operate a vessel within one
hundred fifty (150) feet of a diving buoy except while engaged in the
rescue of a person in such area.