I'm an instructor and evaluator for Delta Society, so I can answer your questions if you decide to go that route. First off, the dog has to be at least a year old before they start visiting. The reason for that is that it gives them a year to grow up a little bit, get a lot of socialization under their belts, and grow out of the puppy stage where they haven't settled down yet, and would rather be jumping around and being silly. Not all dogs are grown up enough at one really, some labs don't seem ready till they're around 3 or so. It just depends on the dog. The handler has to have known their animal for at least 6 months. This gives them time to build the bond that's necessary. What I mean by that is that the animal really has to trust the handler to not put them in a dangerous place. The animal has to trust that their handler will keep them safe, or they won't relax into the job because they'll be on guard, trying to keep themselves safe. Six months gives them enough time to build that bond. It also gives the handler enough time to really know their animal, know their stress signals, and predict how they're going to react to things, so that they can modify the situation if they need to in order to make it a positive experience for everybody.
I would suggest to go ahead and get your cgc during the next 3 months. I did that with Cosita and Liberty. The first part of the test is a lot like the cgc, except you never have to leave your dog. Here are the things they need to know:
Walk on a loose lead
Accept a friendly stranger and remain in control
walk through a crowd
react to distractions like loud noises and walkers in front of them
sit
down
stay in place
come when called
walk past a neutral dog without trying to get to them
be touched everywhere
be impeccably groomed
be petted by someone who is not coordinated and making strange noices
approach a moaning person with a flapping robe and a walker
observe 2 people arguing and approach them after they stop
be petted by numerous people at once
walk past a toy on the floor
accept a treat gently
The evaluator will be observing how you support your dog through this, how you position her, how you alleviate her stress, talk with her, and how much she trusts you. We watch for stress signals during this to make sure she's really enjoying it, and not just doing it because she has to. That's pretty much the test.
The other thing I would strongly recommend is to find a local affiliate of whatever organization you decide to join. They'll have classes, where you learn that it's soooo much more than a "hug a pet" program. You'll learn how best to get your dog on a bed so as not to pull out iv's, how to minimize the spread of infection, how to manage a group of people in wheelchairs so your dog doesn't get a paw run over, etc.
I love this work. I'm so passionate about it that I wrote a book of ideas for people who are already certified. It's at
101 Creative Ideas For Animal Assisted Therapy - Home You'll love it tons too. It's addictive because you'll see little miracles every time you go. If you have any questions I might be able to answer, just let me know!