Here are the facts between your dog wearing a harness or a collar and which one is safer?
Which one is safer?
The truth behind which is safer is actually both! Your dog should wear a collar and harness for specific reasons. The harness is the most appropriate place to attach the leash, keeping your dog secure while eliminating strain on their necks. Also allowing you to have better control over them. It is a lot harder for a dog to slip out of a harness.
When to be worn
Harnesses should be worn during exercise routines like walks or runs. The harness should be loose-fitting as well. Front-clip harnesses work better for the dogs that need more restraint on their walks because they pull on the leash. Head halters should be used when the dog can control themselves. It gives little control over the dog and more to you.
When not to be worn
The collar and harness should both be taken off during play time. They could get caught on things and hurt the dogs while they are playing. This can cause chaffing when they would get caught on objects.
Pros of a harness
They create less stress on the dog and human when they are being walked. Front-clipped harnesses are shown to be the most useful when dogs are in training and teaches them to not pull on the leashes. Harness have a larger variety of sizes, making it easier to find a better fit for your pup. More efficient to use when training a pup so you have better control over them.
Cons of a harness
They still need to be removed when not in proper use, especially when a dog is playing with other dogs or is inside. If a harness is worn excessively they can cause chafing around a dogs' elbows. If the dog is not wearing the correct size it can cause discomfort to your dog. If the harness is the wrong size if can inhibit movement and alter their natural gait.
Pros of a collar
Collar are secure and a comfortable way to keep dog tags on your pup at all times. Either in a leash or not, dogs do notice a simple buckle collar. Collars come in large varieties of types and materials, which can fit specific needs of your dog and make it safer for them. Some collars eliminate the risk of suffocation in an accident by detaching under generalized pressure.
Cons of a collar
Collar are easier for dogs to slip out of and escape. Especially dogs with small heads or dogs that have broad necks. Collars can be hard to fit exactly for tiny dogs. Collars are known to cause thyroid and trachea damages to those dogs who pull. There is a higher possibility for collars to get caught on objects while dogs are playing. They are also known to get stuck in other dogs mouths when they are playing.