Sterile is the total killing of any ALL pathogens (bacteria, fungus, yeast, virus, parasite)
For steam sterilazation it is a minimum of 250 deg F at 21 pounds of pressure for minimum of 15 mins. For open devices like stainless steel instruments 20 to 45 mins or longer for wrapped or packeted instruments.
The other professional forms of sterilization is ETO (Ethylene Oxide ( a deadly poisonous gas ) or gamma irradiation.
Clean is NOT sterile. Washing things off is NOT sterile. You may get things cleaner with sodium hypochlorite (bleach), betadine solution, alcohol and the like but that still is NOT sterile.
I would recommend you do not reuse catheters, EVER. If you are using the same metal instruments only on yourself you can just wash them if they are going in vaginally or rectally, NOT urethrally. Someone was posting about penetrating the cervix, DON'T.
I would NEVER put a urethral sound or catheter in someone that was not sterile. Period. There are some nasty bugs out there now everyone, MRSA to name one. The average UTI is now mostly non responsive to anything but cipro. In short, you are playing with fire.
When you introduce a non sterile item into someone you are in effect breaking the skin barrier as mucosal membrane is not an effective barrier to most bugs.
First and foremost, play safe. If you don't KNOW, don't do. Ask one of us professionals first, before engaging in a procedure you are not sure of. Better safe than sorry.
Dr. B.