I was talking with a client today who relayed a scary situation she just experienced: her two dogs were playing when one of the dog's lower jaw got caught under the collar of the other dog — trapping them both in a panic. If the owner wasn't there to untangle the dogs, one of them would have died of strangulation.
The very same incident happened to us a few years ago and it is panic-inducing, to say the least. Once that happened to us, we never left the dogs at home alone with their collars on.
If you use choke collars on your dog, take them off. You don't need a choke collar first of all. And second, if the ring of the collar gets stuck between the deck, in the heater vent, or even on the edge of the crate, your dog will strangle. Period. Seriously, take the choke collar off and throw it away today. (If you use it because your dog pulls, try an Easy Walk Harness instead — much better at controlling pulling dogs than a choke collar and infinitely more safe for your dog.)
I advised my client to take the collars off the dogs, but she expressed concern that if the dogs got out, they'd be without any identification. That's a valid concern, and I always recommend that dogs not only wear identification on their collar, but are also microchipped as well.
If you're like my client and simply aren't comfortable without a collar on your dog, take a look at these collars by Premier. They are breakaway collars and will release when enough pressure is exerted. That way you can keep your collar on your dog, and not worry about the possibility of strangulation.