Colorado Dive Flags

Rules for CO divers and boaters

If you have any additional Colorado scuba diving links or dive flag info to recommend, let me know.

For Divers in Colorado

Colorado’s require:

Scuba divers must display a warning flag when diving. The flag has one diagonal white stripe on a red background and must be identifiable from 100 yards. Place the flag at or near the point of submergence and divers and stay within a 100-foot radius of the flag.

Colorado Regulation #216 states that the international cod flag “A” or Alpha Flag shall be a “rigid replica” not less than one meter in height. So, as standard signal flag would not comply. Here is a link to the .

Note that this is basically the same as the USCG Navigation Rule #27 which states:

(e) Whenever the size of a vessel engaged in diving operations makes it impracticable to exhibit all lights and shapes prescribed in paragraph (d) of this Rule, the following shall be exhibited:
(i) three all-round lights in a vertical line where they can best be seen. The highest and lowest of these lights shall be red and the middle light shall be white;
(ii) a rigid replica of the International Code flag “A” not less than 1 meter in height. Measures shall be taken to ensure its all-round visibility.

The above information was generously contributed by a visitor to this site, “Rick Waterskier1”


For Boaters in Colorado

Vessels must stay 100 feet from the diver’s flag.

If a vessel is engaged in diving operations, it must display the international code flag “A” or Alpha flag. The flag must be at least one meter in height and blue and white in color. The Alpha flag will warn other vessels that the boat is restricted in its ability to maneuver. The boat’s Alpha flag is required in addition to the diver’s flag.

Happy Diving,
Chris Whitten
chris-(@) (remove the hyphens and parentheses) Webmaster

P.S. The information above was as complete and up-to-date at the time as I could make it. It should not be construed as providing legal advice. You should conduct your own legal research or contact an attorney.