Rotating Inner Drum Autoclaves (RIDAs) are used for sterilizing or steam processing regulated medical waste (RMW) and other non-homogeneous solids or slurries which would entangle any other device that uses an agitator.  The inner drum contains spiral flights that help the contents mix and tumble when the drum rotates. Because the flights are in a spiral configuration, the inner drum loads when rotated forwards; but when the drum is rotated in reverse, it completely self-empties all solids and liquids.


Stationary autoclaves require a very long time for the center of a one cubic meter cart to reach sterilization temperatures. In comparison, imagine how long it would take to cook a 100 kg. cake. The tumbling action of the inner drum exposes all of the processed material directly to steam which heats it almost instantly. Most users run a 1 hour cycle which uses approximately 1/3 kg of steam per kg of RMW.

This table lists Liberty Welding and Bartlett Engineering's two popular hospital sized models and the key design parameters.  We have designed and manufactured over 150 units scattered to all corners of the world such as US, UK (with EU CE marking per PED guidelines), Japan, Saudi Arabia, Qatar, China (with ML), and Mexico.  Our ability to remotely troubleshoot the control system is particularly helpful for those machines that are in other countries or remote locations.

RIDA table.jpg

Every RIDA system comes with a performance guarantee that it can achieve a microbial inactivation of STAATT (note 1) Level IV, which translates to a reduction of bacterial spores by at least a factor of 1,000,000:1, commonly referred to as 6log10 or 10^6 (note 2). This level is considered "sterilization." Some competing units which are rated for STAATT Level III achieve a reduction factor of 10,000:1, which is considered only "inactivation."

note 1: STAATT  - State and Territorial Association on Alternative Treatment Technologies
note 2: Bacterial spore reduction measured using geobacillus stearothermophilus as biological indicators.

© 2020 Liberty Welding and Iron Works Co.

101 N Causeway Blvd Metairie, LA 70001

Email: sales@liberty-welding.com 

Phone: 504-457-3200

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