Sterilization of various diameter dead-ended tubes
Related Experiment Video
Updated: Jul 3, 2026

An In Vitro Hemodynamic Loop Model to Investigate the Hemocytocompatibility and Host Cell Activation of Vascular Medical Devices
Published on: August 21, 2020
1The Pennsylvania State University at Erie, The Behrend College, Erie, Pennsylvania 16563, USA.
Abstract:
Effect of tube diameter on steam-in-place sterilization of dead-ended tubes was studied by examining temperature profiles and rates of kill of Bacillus stearothermophilus spores. Time required for sterilization was determined for 9.4-cm-long tubes with various inside diameters from 0.4 to 1.7 cm. Sterilization time increased with decreasing tube diameter. Experimentally measured kill kinetics in 1.7-cm tubes were in agreement with those predicted if measured temperatures represented saturated steam. A 12-log spore reduction was achieved in 1.7-cm diameter vertical and horizontal tubes in less than 63 minutes. For smaller diameter tubes, entrapped air remained after 2 hours and rates of kill were very dependent on position within the tube, tube diameter, and tube orientation with respect to the gravitational vector. Times to achieve a 1-log drop in spore population in the smaller tubes were as much as 10 times greater than those expected if measured temperatures represented saturated steam. Sterilization was not achieved throughout the 0.4-cm tubes. Recommendations are made for including steam bleeders or using prevaccum cycles for these smaller diameter tubes.
More Related Videos
Related Concept Videos
Methods of Sterilization I: Physical Methods
Steam sterilization uses non-toxic, low-cost moist heat in the form of saturated steam under pressure, which is fast, microbicidal, and sporicidal, and quickly warms and penetrates fabrics. Autoclaves, or steam sterilizers, expose each item to direct steam contact for a predetermined time at the necessary...
Methods of Sterilization II: Chemical Methods
Using chemical sterilization rather than heat to clean out equipment is recommended. It eradicates and removes all bacteria,...
Cleaning, Sterilization, and Disinfection
Cleaning
The cleaning process usually involves using water with detergents or enzymatic cleaner and removing foreign material from objects and surfaces, including organic material such as body fluids or inorganic material like soil. Cleaning is performed before high-level disinfection and sterilization because foreign materials on the cover of the devices interfere with process...
Physical Methods for Controlling Microbial Growth: Radiation and Filtration
Physical Methods for Controlling Microbial Growth: Temperature

