1. Is this also safe for pets? 2. We are looking to install on concrete.....is it necessary to apply adhesive if swingset will be on top? If so, does the adhesive cause damage when removing the artificial grass later?

Yes, these turf rolls are pet-friendly. Using adhesive is recommended if you're looking for a more permanent install. When removed, it wouldn't damage the subfloor but may leave adhesive marks that could be removed using a soap & water solution. Alternatively, you may simply use a double-sided tape along the perimeter of the turf, to keep it in place.