Properly Sizing an Autoclave Chamber for Your Animal Lab Written by: Mike Peters Steam sterilization is routinely used in animal laboratories for two reasons: 1) to sterilize animal cages in order to create a pathogen-free housing environment and 2) to properly dispose of harmful waste products. Since autoclaves are essential for everyday laboratory operation, it is important to select a chamber size with enough capacity to meet the lab’s demand for cage and waste processing. Under-sizing the autoclave will leave it insufficient to meet the lab’s demands while an oversized autoclave takes up valuable lab space and carries a higher upfront cost. An animal lab facility should consider two primary factors before making a sterilizer purchasing decision: The facility’s Animal Biosafety Level requirement The number of animal cages that need to be processed What are my Animal Biosafety Level requirements? The ABSL rating of a particular animal lab can influence cage sterile processing procedure, which impacts throughput. For example, consider the process flows for two laboratories, one ABSL-1 and one ABSL-3, changing out the same amount of cages per week. Although both labs are processing the same amount of cages, the ABSL-3 laboratory has over twice the sterilization demand. In addition to autoclaving the fully assembled cages (the final step), an ABSL-3 lab must also perform two additional autoclave cycles: one for the cages before washing and one for the soiled bedding. It is important to note that after emptying the soiled cages in a biological safety cabinet (BSC), they can be nested together (see Figure 4) to allow more cages to fit in the autoclave chamber. After washing, the cages are sterilized fully assembled with bedding (see Figure 3). How many cages need to be processed? The first step in determining the required autoclave chamber size is figuring out how many cages are changed at a time. This estimation depends on the total number of animals in the facility and their size.[1] After you have established an estimate for how many cages need to be changed, consider that a standard mouse cage is approximately 7.5” x 11.5” x 5”. From here, you can approximate chamber dimensions to handle the amount of cages you need to sterilize per load. For example, 80-96 fully assembled mouse cages can comfortably fit in an autoclave with chamber size of 36” x 48” x 72” (see Figure 3). Figure 3: Assembled Cages Figure 4: Nested Cages It is essential for an animal laboratory to select an adequate chamber volume for their autoclave. If the volume is too small, the lab will be limited to how many cages they can process per week. On the other hand, purchasing an unnecessarily large chamber is a needless expense. Analyzing cage processing procedures and estimating how many total cages are used can give animal labs a good estimate of their required autoclave chamber size. Please consult Consolidated Sterilizer Systems if you have any questions or concerns about vivarium sterilization. [1] See The Guide for the Care and Use of Laboratory Animals housing space requirements for mice in groups. Table 2 The Center for Disease Control created ABSL to establish standards for quality, safety, and care in the laboratory. The table below provides a summary of the containment levels, autoclave design requirements, and cage processing procedures. Table 1 Don't Buy An Autoclave Until You Read This Find out the 17 questions you need to ask before buying your next autoclave. Download eBook Tweet Like Share
Properly Sizing an Autoclave Chamber for Your Animal Lab Written by: Mike Peters Steam sterilization is routinely used in animal laboratories for two reasons: 1) to sterilize animal cages in order to create a pathogen-free housing environment and 2) to properly dispose of harmful waste products. Since autoclaves are essential for everyday laboratory operation, it is important to select a chamber size with enough capacity to meet the lab’s demand for cage and waste processing. Under-sizing the autoclave will leave it insufficient to meet the lab’s demands while an oversized autoclave takes up valuable lab space and carries a higher upfront cost. An animal lab facility should consider two primary factors before making a sterilizer purchasing decision: The facility’s Animal Biosafety Level requirement The number of animal cages that need to be processed What are my Animal Biosafety Level requirements? The ABSL rating of a particular animal lab can influence cage sterile processing procedure, which impacts throughput. For example, consider the process flows for two laboratories, one ABSL-1 and one ABSL-3, changing out the same amount of cages per week. Although both labs are processing the same amount of cages, the ABSL-3 laboratory has over twice the sterilization demand. In addition to autoclaving the fully assembled cages (the final step), an ABSL-3 lab must also perform two additional autoclave cycles: one for the cages before washing and one for the soiled bedding. It is important to note that after emptying the soiled cages in a biological safety cabinet (BSC), they can be nested together (see Figure 4) to allow more cages to fit in the autoclave chamber. After washing, the cages are sterilized fully assembled with bedding (see Figure 3). How many cages need to be processed? The first step in determining the required autoclave chamber size is figuring out how many cages are changed at a time. This estimation depends on the total number of animals in the facility and their size.[1] After you have established an estimate for how many cages need to be changed, consider that a standard mouse cage is approximately 7.5” x 11.5” x 5”. From here, you can approximate chamber dimensions to handle the amount of cages you need to sterilize per load. For example, 80-96 fully assembled mouse cages can comfortably fit in an autoclave with chamber size of 36” x 48” x 72” (see Figure 3). Figure 3: Assembled Cages Figure 4: Nested Cages It is essential for an animal laboratory to select an adequate chamber volume for their autoclave. If the volume is too small, the lab will be limited to how many cages they can process per week. On the other hand, purchasing an unnecessarily large chamber is a needless expense. Analyzing cage processing procedures and estimating how many total cages are used can give animal labs a good estimate of their required autoclave chamber size. Please consult Consolidated Sterilizer Systems if you have any questions or concerns about vivarium sterilization. [1] See The Guide for the Care and Use of Laboratory Animals housing space requirements for mice in groups. Table 2 The Center for Disease Control created ABSL to establish standards for quality, safety, and care in the laboratory. The table below provides a summary of the containment levels, autoclave design requirements, and cage processing procedures. Table 1 Don't Buy An Autoclave Until You Read This Find out the 17 questions you need to ask before buying your next autoclave. Download eBook Tweet Like Share
12.10.25 Introducing SterilSteam Sampler, The Steam Condensate Sampler for AAMI ST108 Compliance → Released in 2023, AAMI/ANSI ST108 establishes water quality requirements for water used in the cleaning, rinsing, disinfection, and sterilization of reusable medical devices. In addition to these requirements, ST108 mandates quarterly testing of steam condensate quality to ensure incoming steam does not stain instruments or pose a risk to patient safety. To help healthcare facilities […]
11.6.25 AAMI ST108 & Critical Water for Autoclaves: What ASCs Need to Know → A major step forward in patient safety, ANSI/AAMI ST108 establishes new minimum water quality requirements for water used in the cleaning, rinsing, disinfection, and sterilization of reusable medical devices. Despite providing guidance on water quality management for sterile processing, ST108 has also created confusion, especially regarding test protocols, water treatment, and critical water requirements. In […]
10.20.25 What Is an Autoclave Machine Really Used for? [Applications, Costs & More] → Autoclave machines are mission-critical equipment in a variety of industries, from healthcare to biotech, ensuring equipment and materials are sterilized and safe for use. Whether you’re considering purchasing an autoclave for a new facility, replacing a broken one, or expanding your current sterilization capacity, understanding the ins and outs of autoclave technology is key to […]
