Such dogs are going to be inherently well behaved. I would think your main concerns are around phobias and allergies. The welfare of the dog should be easily dealt with though you will need to think about time for 'walkies' and then disposal of the bag....

Hi Brian,
I've ben asked a few times about guide dogs for blind employees. Hearing dogs also get a lot of training so are very unlikely to 'attack' as previous replies have mentioned their good behaviour. If anyone is allergic the dog will have to wait in another room until work is over. This of course means that full use of the dog won't be able to happen. You could perhaps consider other room options. We all fight to take Wanda (Barbara's guide dog out) which is usually once mid morning, lunch time, mid afternoon and sometimes just before she goes to get the train home. Probably more than is needed but it actually gives us a welcome break and some fresh air. We have a grass area belonging to us which we use (or Wanda does!)
The dog will be trained to warn its owner of a fire alarm and shouldn't really pose an obstruction so really shoul dbe close by or other procedures put in place.
Wanda has her toys in the office and she often drops them in the middle of the floor so we're often putting them to the side. No-one minds though and toys aren't compulsory!. As Wanda is a lab x retriever she does cast hair and our cleaners have to be more vigorous with the hoovering at that time. When its raining you can also get a doggie smell from their hair and some 'tummy smells' but again we all don't think this is a problem. This was discussed wiht exsitng employees and any new employees are asked when the start (not at interview so that no-ne sees this as a barrier to them getting the job).
I shol dhave said that we poopy pick (Barbara can't see the pooh) but that's just a couple of us and others don't have doggies ad aren't keen onthis aspect. We put the bags into the main bin which is on way back from garden.
You'll need to watch titbits as they can get too many.
If someone was reaaly afraid of dogs we would try to resolve this by office positioning, dogs access to areas and possibly dog awareness? It's never actually arisen even though we have a couple of people bit that fond of dogs they don't mind Wanda being there.
A big plus for us is that Wanda loves people and we all love petting her. I consider her a therapy dog.
Hope this helps, Lilian