Want to spray fly killer - Is there a dog friendly one?

I've put this in home/garden but is also dog related.
We seem to be inundated with flies at the moment and they're driving me crazy! I've killed 8 in the last hour. Does anyone know of a product I can spray the yard with without it harming Cassie? She's pretty good about not eating/licking stuff she shouldn't but don't want her breathing in nasty stuff either. Anyone have any ideas?
Thanks