im almost sure the law states you must have the flag with you.it was brought to my attention after my shore dive to the y.o. now common sense should tell you to tow the float (with flag) in the event that something should go wrong. as a responsible diver it is good practice to always consider safety first(yea i admit it i used to take big risks for the sake of a dive stopped that stuff along time ago) As a Dive professional (DM) I suggest that you get a float attach a flag to the float then use a reel so that you can feed out line according to your depth. you said we that means someone else will be diving with you . how often divers get seperated ? happens all the time that flag is the easiest way to find your partner. hard to believe that there is an IDC instructor here telling you otherwise. im so sure that the advise he has given you is in keeping with PADI standards.amazing. its your life you can play craps with it all you like. it must be ok cause three dive instructors and a scuba board staff member all say its ok. hmmm i wonder what would be the legal liability of sb if something went wrong. I truly hope you reconsider towing the flag, not because its the law but because its a matter of safety so many things can go wrong and that float would be of use to many of them remember most diving accidents start out as something small then grow .please enjoy your trip.
I LINKED to the DLNR/DOBOR copy of the HRS quoted where it clearly states that there is "no subsurface distance restrictions". This means that you do not have to be with your flag. But you must surface within 100' (or 50' if in a navigable stream).
If you are not within 10-15' of the surface, there is no safety risk from not having your flag.
Besides... what benefit is the flag if the buddy that wants to find the other "lost" one is the one with the flag?
PADI standards only apply during training events. What divers do on their own should fall under the Standard Safe Diving Practices, which includes obeying local laws and is EXACTLY what I'm advocating here.
If buddy separation "happens all the time" for you, I'd revisit either a) your diving practices or b) your choice of buddies. Or perhaps both.
As for local practices on Maui, towing the flag is an exception. Shaka Doug does it always, as do the instructors at the Maui Prince (because their path crosses paths with the Kai Kanani as she loads/unloads from shore). And that's pretty much it. The only other people I've seen drag a flag the entire dive here have been doing a drift dive.
So, regardless of what you read here, you'll find that local practice, which is within the bounds of the law, is exactly what's being advocated -- hence absolving any legal liability on recommendations posted here.
Oddly enough -- the only issues I've heard of with regards to encounters with vessels in these waters have been when there IS a flag immediately above the divers. The boaters don't know what it means, and approach to investigate... and the jetskiers use them as slalom buoys.