Unfortunately there isn’t, we can only assess the surface damage to the helmet and give our opinion. From our experience of racing and road accidents you are often best placed to make a decision on whether to continue using your Arai as you were wearing it at the time.
Arai shells are made to be really strong so a drop from a low height is usually fine depending on the surface of course. The part of the helmet you can’t see is the EPS polystyrene liner; this absorbs energy during an impact, and as this is not removable there is no way of telling if the helmet has been damaged internally. Again, you are the best person to judge whether the helmet will be safe or not, if in any doubt buy a new helmet!