An autoclave is an essential tool in many industries from waste management to health and personal care industries. Understanding its place in medical waste can help you determine the most strategic approach for your facility's waste needs.

01   /  What is Autoclave?

Autoclaving is a steam sterilization process that medical facilities can use to sterilize small equipment, tools, or waste. An autoclave machine does this by using high-temperature and high-pressure steam to kill microorganisms in the waste. These autoclaves are often used in laboratories, hospitals, pharmaceutical facilities, veterinary facilities, and medical offices. 

There are many different types and sizes of autoclave machines available, all of which offer the same benefit of killing microorganisms. Facilities can set the autoclaves to different temperatures and have them run through more than one cycle. The machines also offer a variety of features, including vacuum functions and special cycling. For most healthcare facilities, an autoclave machine is a vital piece of safety equipment.

02   /   What is Autoclaving and How Does Autoclave Sterilize Medical Waste?

According to the Centers for Disease Control and Prevention (CDC), steam kills microorganisms through “the irreversible coagulation and denaturation of enzymes and structural proteins.” So, autoclaves can kill these microorganisms by breaking down their essential components through the use of heat. The time it takes to do this varies and depends on the temperature of the steam.

Here are the steps in the autoclaving process.

  1. Purge Stage: Waste is first placed in an autoclave machine’s biohazard bin. The machine fills with steam at the set pressure and temperature for the chosen period of time. This is typically from 30 to 60 minutes.

2. Exposure Stage. In this step, the exhaust valve closes, and the pressure and temperature increase. Then, the waste will be exposed to the steam for a set period of time. The time the autoclave needs to run is generally determined by state regulations. The temperature of the steam will generally be set from 250 to 300 degrees Fahrenheit.

3. Exhaust Stage: During the exhaust phase, the pressure is released from the chamber, and the temperature goes back to its original setting.

Medical facilities have many options when it comes to autoclave machines, including a variety of sizes. Autoclave machines can hold anywhere from 40 to 1,000 liters. This means that any facility, no matter how big or how small of a waste generator they are, can find the right autoclave to fit the needs of their location.

03   /   Medical Autoclave Requirements

Medical autoclave requirements vary in the US from state to state. Georgia, for instance, has specific requirements for medical waste to be sterilized in an autoclave. All biological waste must be in the autoclave for a minimum of 30 minutes at 249 degrees Fahrenheit (121 degrees Celsius). The CDC recommends a temperature of 250 or 270 degrees Fahrenheit when using steam to sterilize for infection control in order to make sure microbes are destroyed. They state that the time necessary for sterilization will vary according to the types of items being sterilized.

Medical facilities typically use autoclaves to sterilize regulated medical waste. The facility uses the autoclave by placing the waste to be sterilized in the autoclave and closing the door. After this, a vacuum pump removes the air from the chamber and steam is forced into the cavity to achieve the proper temperature for microbes to be killed. Once the process is completed, the door is not opened until the pressure is back to zero. At this point, the waste has been sterilized and is no longer an infection threat, allowing it to be disposed of with general waste and shipped to a non-hazardous landfill.

04   /   What Is Biomedical Waste?

There are many definitions of biomedical waste. It can vary by state or even city. In Georgia, for example, medical waste is solid waste and includes the following:


Pathological waste


Biological waste


Cultures and stocks of infectious agents and associated biologicals


Contaminated animal carcasses, body parts, their bedding, and other wastes from such animals which are infected with or which have been exposed to infectious agents that could cause disease in humans




Chemotherapy waste


Discarded medical equipment and parts

05   /   Examples of Biomedical Waste

Biological waste is also called red bag waste or regulated medical waste. This type of waste is made up of items that either could be or are contaminated by certain bodily fluids, such as blood or other materials that are potentially infectious. Some items frequently found in hospitals or doctors’ offices that could be sterilized in an autoclave are:


Personal protective equipment: Gauze, gloves, gowns, or other items doctors, nurses, or patients might wear 


Contaminated or used sharps: Items that could break the skin, such as syringes, medical knives, needles, or scalpels


Potentially contaminated items: Bedding, gauze, suctioning, used bandages, and other items that might be contaminated by bodily fluids

06   /   Items That Should Not Be Treated in an Autoclave

Autoclaves are effective for treating many types of biological waste. Temperatures in these machines typically range from 250 to 325 degrees Fahrenheit, and this is sufficient for most types of regulated medical waste. But, it is not a good method for treating hazardous materials, such as chemotherapy waste, expired medications, or pharmaceutical waste. Hazardous materials should be incinerated. Incinerators use higher temperatures when treating these materials, thus destroying them so they can be sent to a landfill without the worry that they may leach into the surrounding soil or groundwater.

07   /   Ensuring Effective Autoclaving

Autoclaving is a common method for treating medical waste, but it is important to take some precautions to make sure the process is effective. Here are a few of these precautions.


Do not overload the autoclave or the autoclave bags. It is essential that the steam be able to circulate and reach all items in order to properly sterilize them.


Be careful when sterilizing sharp objects as they could puncture the autoclave bags.


Do not open the door until the drying is completed.


Keep up-to-date on autoclave maintenance.

08   /   Be Aware of Autoclaving Regulations

Medical waste companies must have the appropriate insurance and permits to legally provide certain services, including autoclaving. Reputable companies such as MCF Environmental Services have both of these. MCF maintains compliance and has the expertise necessary to provide your facility with advice in many areas of healthcare waste management, including autoclaving. If you’re curious to learn how your facility can more efficiently handle medical waste, reach out to our expert team for guidance and insight.

Robert Losurdo

President, COO