The autoclave is one of the most important sterilization tools in medicine. But it’s also one of the most misused. Steam, heat, and pressure work together to eliminate microorganisms, but they also destroy certain materials just as effectively. Knowing the difference between what you can and can’t put in an autoclave keeps your equipment intact, your staff protected, and your sterilization process effective.
Materials That Belong in the Autoclave
Most heat- and moisture-stable materials handle autoclave conditions without issue. These include the following:
- Stainless steel instruments, like forceps, scissors, and clamps, are ideal candidates. They tolerate high temperatures and repeated cycles without degrading.
- Glassware used in lab settings, including beakers, flasks, and Petri dishes, can be autoclaved as long as they’re borosilicate glass. Regular glass can crack under thermal stress.
- Textile items, such as surgical drapes, gowns, and wrapped instrument trays, autoclave well when properly prepared. Wrapping material needs to be permeable to steam for the cycle to work correctly.
- Certain plastics are autoclavable, but you need to verify compatibility before assuming. Polypropylene (PP) and polycarbonate (PC) generally hold up, while polyethylene and polystyrene don’t.
- Biohazardous waste and contaminated media can be deactivated in the autoclave before disposal. You’ll want to follow your facility’s specific protocol for waste bags and container types.
Items You Should Never Autoclave
Some materials react badly to the autoclave environment, and putting them through the machine is among the most common autoclave usage mistakes. Autoclaving incompatible items can damage the equipment, create hazardous byproducts, or cause sterilization failures.Here are the items that most mistakes happen with:
- Sharp, non-stainless metals can corrode when exposed to steam repeatedly. Carbon steel instruments are a common example. If your instruments aren’t clearly rated for autoclave use, don’t assume they are.
- Flammable or volatile substances have no place in an autoclave. Alcohols, solvents, and any flammable liquid can combust under heat and pressure.
- Chlorine bleach and bleach-containing solutions must stay out. Chlorine vaporizes during a cycle and can damage the chamber’s internal components.
- Radioactive or chemotherapy materials require specialized disposal processes. The autoclave doesn’t neutralize these hazards.
- Non-autoclavable plastics, including polystyrene and polyethylene, will melt or off-gas toxic compounds. Check manufacturer specifications before loading any plastic item.
Keep Your Process Sharp
Understanding what you can and can’t put in an autoclave is a key part of protecting patient safety, instrument longevity, and regulatory compliance. The more consistently you or your team applies this knowledge, the fewer sterilization failures you’ll deal with.
