Therapy Dogs?

Has anybody volunteered with their dog as a therapy dog? There's an organization in my city where they take groups of people with their dogs (and cats) to hospitals, senior's homes, etc. I was wondering what more I could do with my dog to get him prepared for the tests. We passed the basic application and next is my interview, then his interview. Any tips or practical advice would be great!

P.S He does all the basic commands, is calm on leash and adores children. He's met people with canes and passed people in wheelchairs, nothing seems to faze him besides loud noises which I'm working on.

Thanks!

Common tests involve popping an umbrella near your dog and dropping a stainless steel bowl on the floor. Also passing by a plate of human cookies at dog level, or child's stuffed animals and your dog is expected to leave either alone.

Dog also generally has to pass by another dog same side no human in between and be friendly but show little interest

Not every organization is the same.. but here's TPOC's test http://www.tpoc.ca/TherapyDogEvaluation.aspx

I want to see if my pup will be acceptable as well - I wish to begin a pet therapy program at the mental health centre. There is no organization in this town as far as I know. Who should I contact? How old does my dog have to be? :)

Often a year minimum. TPOC that I linked to and St John's Ambulance are the main therapy dog organizations in Ontario.