safe space for kids with sen needs

My son harry has autism and global development delay, he's managed mainstream school so far, currently they are having major issues in school with him so a safe space would be ideal to be able to keep him safe when having self harming meltdowns, his school st Helens primary academy are a fantastic school and take in more special needs kids then I can count so this isn't just to help my own son but many like him already there and the many more they will take in over the years , please any small amount will be very much appreciated