Yeah, as my friend said "The dogs learn quick" and she's right. My 9 month old mutt used to love to accompany me to the hive. She's snap at the flying bees, and I'd tell her no, and she better watch out. Then one day she stuck her nose right into a cluster of bees on the cover I had removed. Woot, did she move with a quickness! She scampered away and chased her tail all the way back to the house. Luckily I have sweet bees and they didn't follow her. Her nose swelled up a little, but I gave her a benedryl and she was fine by the next morning. She stays away from the hive now, even when I'm working them.
The only thing I'd worry about is the size of your dogs. If they got stung on the nose, not sure how much it would swell since the proportion of venom would be higher. as long as they didn't swarm after them I'd think they'd be ok, but if your bees are touchy or your dogs rambunctious, might want to keep them inside when you're working the hives.
Hope that helps.
Love,
ziffa