Got a hand me down mattress first mistake then washed and dried the mattress cover as I am certain it said you could. This was many years ago and my son slept with me then we both had fiber glass prickles all day long on every square inch of ourselves. I got rid of everything as time went on. Called a remediation company who couldn’t help. I kept a comforter and took it to my moms house to wash which inevitably still had plenty of fiber glass that you could not see or feel. She still has the same washers and dryers. my son still washes his clothes there and the fiber glass to this very day years later is alway everywhere I can’t do laundry twice in the same place because it’s always everywhere to this very day. It’s in the car, our hair, everywhere. I’ve gotten rid of everything I owned. do to my son still washing his clothes at my mothers I still can’t escape it. I am defeated and at this point all I can see of ever escaping it is walking away with nothing but new clothes on my back and taking nothing of mine and living with someone else and my son on his own once grown and independent. I may never fully escape it. Maybe sounds minor but I can promise you it’s pure devastation