Vibration and weight parameters

[Jen Fredrick]

Hello everyone!   I work at a school for children with autism.  We use a variety of mini-massagers to provide sensory input for our children.  Is anyone aware of any parameters regarding how much vibration, if any, is ok to provide to a child's face?  Should any input be directed by the child only? Or is it ok for the therapist to provide it to the child, if they are craving input of any kind to their face?  Is it a bad idea to use a mini massager on a child's back, even if that is the input they are seeking? (The massager in question is a small, handheld device with a bumpy ball on it)   Also, I know there are suggestions for how much is too much weight for a child's backpack.  When doing heavy work, like pushing weighted baskets, are there any guidelines for how much weight to put in, such as a child's weight to bucket weight ratio?   I would appreciate any suggestions, or referrals to specific sources.  Thank you!   Jennifer Fredrick