My husband works for a pest control company and it basically depends on what they were trying to treat. If it was mice then it shouldn't be a problem, if it was bed bugs then you would want probably clear out for the night. Was it something they treated inside the house or outside the house?
Hmmmm, we just got a nontoxic treatment done at my house (derived from chrysanthemums, considered perfectly safe around pets and children) for ridiculously persistent black ants and the company still wouldn't do the inside of my house knowing I was pregnant without me clearing out for two hours. I suggest you call the company asap.
Re: Is it safe