Don't have DWAN access, but off the top of my head, the NAVFORGEN basically said, if you are at a sea going unit (or otherwise may have to wear the air pack for fire fighting) you need to be clean shaven.
CANFORGEN basically says everyone in the CAF can now grow beards to the old Navy standard (barring specific operational requirements), so there isn't any conflict. The RCN has put down a single standard for the operational units, so pretty straightforward. Otherwise every single ship/navy unit would have their own set of rules, and that would be kind of dumb, as well as confusing as you jump between ships.
People will argue about the validity of the logic, but even if some people get a seal with a beard, some won't be able to. Being clean shaven will never interfere with the seal, so it's erring on the side of caution. Best case, your seal fails, and you are able to safely get out of the area. Smoke spreads really quickly though, so it may take you a while, and smoke inhalation sucks. Now you've left the rest of your team sitting around waiting for a replacement, giving the fire time to grow, and generally putting everyone at greater risk. Worse case you run out of air in the fire zone, become a lesson to others, and have your wingers risking their lives to save you.
Fires happen on ships all the time, have been involved with a half dozen myself, and there are tonnes of near misses. The entire surface fleet is currently about 25 years old, (with some older), so even with the pretty active safety program, the failure rates leading to fires is only going to go up, so there is very good operational reasons to keep people clean shaven and trained to respond to fires. My :2c: (based on actual fire science, performance of the BAs with beards, and first hand experience with multiple fires on ships).
