Jar sterilization question

I have grown shrooms successfully a few times using the brf. I was going to move up to using wbs and going bulk. Now I understand that you have to use a pressure cooker for sterilization because boiling may not clean it completely. Now all that is cool, I'm getting a pressure cooker tomorrow. But I was wondering, what would they use in a lab or whatnot to sterilize their substrates? How do they do it? I tried to find a good scientific type video, but all I can find is the typical kitchen chemist.

an autoclave probably in a lab, or a set and forget PC like an AA. but a home PC would do the same job. Make sure it goes to 15 psi or you have to adjust cook times