Autoclaves are used to sterilize biological materials before disposal. If steam isn’t reaching the items being autoclaved, then the items are not getting decontaminated. Proper packaging of materials and cycle selection (to reach appropriate temperature, pressure, and steam) are crucial for successful decontamination. Hazards associated with autoclaves include explosions, burns, shattered contents, and emission of toxic fumes.
Read the Operator Manual and request training prior to operating any autoclave. Check the compatibility of materials including chemicals, electronics, and some plastics because many are not permitted and will emit toxic fumes. Make sure the autoclave’s exhaust is on before use. NEVER autoclave bleach-treated items (toxic chlorine gas will result). Elevate materials away from the drain by using a rack and use polypropylene or metal pans to hold your materials.
Loading and Unloading Materials
If autoclaving bagged waste, make sure the bag is loosely taped so that steam can enter through the bag opening or add water so steam is generated inside the bag – if you tied too tightly, the bag can break open and leak out whatever is inside. Make sure containers with liquids are loosely capped and only half filled to avoid exploding the vessel that contains the liquid and to prevent boiling over.
Before unloading the materials from the autoclave, wait at least 2 minutes after the steam pressure gauge has reached ZERO, and allow it to vent steam out slowly (with the door only open a few inches) before you fully open the door. Use the door to protect your body and don’t lean over to see what’s inside.
Personal Protective Equipment (PPE)
Wear a lab coat, foot protection, and long-sleeved autoclave mitts at a minimum. When handling liquid, the addition of a face shield and apron is appropriate.
Maintenance and Cleaning
Ensure that the drain is clear and the door gasket is in good shape (no cracks, etc) because autoclave won’t be able to decontaminate anything if the drain is clogged. Intermittently test the efficacy of your autoclave runs by using chemical steam integrators (no incubation) and biological spore strips (incubation required). These tests help the most when used in combination and on a regular schedule. Also make sure your autoclave is receiving annual maintenance. For assistance with developing a testing schedule, contact EHS.
Things to Avoid
- Do not use damaged glass items (such as a cracked flask)
- Do not over-pack the autoclave or the bags/containers going in.
- Do not allow items to touch hot autoclave surface or cold surfaces after removal.
- Do not autoclave electronics, batteries, volatile chemicals include bleach, or other materials that can emit toxic fumes
- Read more about decontamination in Section 3.4 of the Biosafety Manual
- You can request training from experienced operators in your department or the vendor
- Video that provides an overview on Autoclave Safety
- Video on the use of Biological Indicators