Steam Sterilization for Medical Equipment

History of Steam Sterilization

French-born physicist Denis Papin invented a prototype of the autoclave called the steam digester, also known as the pressure cooker, in 1679.¹ An autoclave is another term for the steam sterilizer.

Benefits of Steam Sterilization

Steam sterilization has many benefits as a sterilization method in healthcare facilities including low cost, safety, and efficacy. When processing heat and moisture stable materials, the speed and productivity of a steam sterilizer are advantages over other forms of sterilization. Medical devices that can be processed in a steam sterilizer include surgical instruments, implantable medical devices and surgical linens. Sterile Processing Department staff should always follow the device manufacturer's instructions for use when processing the device. Steam sterilization is considered a reliable and consistent method of sterilization throughout healthcare facilities.

Explore our Steam Sterilizers

Steam Sterilization Process

Steam sterilization is achieved by exposing the items to be sterilized with saturated steam under pressure. Steam enhances the ability of heat to kill microorganisms by reducing the time and temperature required to denature or coagulate proteins in the microorganisms. Steam sterilization cycles generally have three phases including conditioning, exposure and exhaust.²

• Conditioning occurs at the beginning of the cycle. Air is removed from the chamber by Gravity displacement or Dynamic Air Removal methods and the load is heated to the recommended sterilization temperature.
• Exposure begins after the conditioning phase when the chamber and load have reached the necessary temperature for sterilization. The items in the load are exposed to steam at a set temperature for a set time. Exposure times and temperatures should be set to follow the device manufacturer's recommendations and in accordance with existing standards and guidelines.
• Exhaust is the last step in the sterilization cycle when steam is removed from the chamber and the pressure inside the chamber is released. It is also known as the cool-down or drying phase. During this phase, a vacuum is drawn to remove the steam and to help dry the load.

Factors that play an important role in the success of the steam sterilization process include proper steam system construction and maintenance; utility supply, including good steam and water quality; steam boiler and sterilizer performance; instrument preparation, wrapping and loading technique and post sterilization handling.²

Steam Sterilization Temperature Guide

Ensuring that the steam sterilizer chamber reaches and stays at a certain temperature for the recommended amount of time is vital to effective steam sterilization.

Some commonly recommended temperatures for steam sterilization are 250° F (121° C), 270° F (132° C), and 275° F (135° C). Typical cycle time and temperature recommendations are defined and tested by the steam sterilizer manufacturer, and vary depending on the type of load being processed. It is important to refer to the manufacturer's guidelines in the sterilizer operator manual before processing a load.

Where to Buy Steam Sterilization Equipment?

The selection and purchase of a steam sterilizer is an important process to a healthcare facility. To keep patients safe and to stay compliant and productive, a steam sterilizer must keep up with the demands of a busy Sterile Processing Department (SPD). Facilities often consider factors like brand reputation, service support, cost and environmental footprint when deciding on a steam sterilizer purchase. Because of the vital role steam sterilization plays in a hospital, Ambulatory Surgery Center, or other healthcare facility, buyers generally research multiple options before making a choice on a sterilizer. The buying process for a steam sterilizer is typically done through a sales representative or distributor.

^{1 https://www.britannica.com/technology/autoclave
2 https://university.steris.com/course/understanding-steam-sterilization}