What is causing these tiny red spots on my arms when I work with dogs?

I started a new career as a dog groomer about one month ago and almost every day i get these tiny red spots on my forearms in randoms areas. They don't itch and they are not raised in any way. As soon as i start heading home they disappear. Ive owned dogs before and have no other reactions to them i would ociate with allergies. Any idea what this could be?