PT  - JOURNAL ARTICLE
AU  - Soham Shah
AU  - Sara Alayli
AU  - Yiming Peng
TI  - Factors Affecting Measurement of Equilibration Time of Dry Goods Loads in Autoclaves
AID  - 10.5731/pdajpst.2018.009225
DP  - 2019 Jan 01
TA  - PDA Journal of Pharmaceutical Science and Technology
PG  - pdajpst.2018.009225
4099  - http://journal.pda.org/content/early/2019/02/05/pdajpst.2018.009225.short
4100  - http://journal.pda.org/content/early/2019/02/05/pdajpst.2018.009225.full
AB  - Equilibration time of an autoclave is defined as the period of time that elapses between the attainment of sterilization temperature at the reference measurement point of the autoclave chamber and the attainment of sterilization temperature at all measurement probes within the dry goods load placed within the autoclave during a sterilization cycle. Equilibration time is an indicator of the ability of the autoclave to remove air from and subsequently sterilize the dry goods load placed within the autoclave chamber. Therefore equilibration time is an indicator of the efficacy of an autoclave cycle. Periodic measurements of equilibration time and evaluation of the equilibration time data can assure continued efficacy of the autoclave cycle. For autoclaves that support biopharmaceutical manufacturing plants, equilibration time is generally measured by placing heat penetration probes within dry goods load items placed within the autoclave during a sterilization cycle. However, equilibration time measured in this fashion yields results that are highly variable and difficult to replicate. This paper presents a study that attempts to understand the impact of the following autoclave variables on consistent measurement of equilibration time and reduction of equilibration time: 1. Type of dry good load item placed inside the autoclave 2. Location of the heat penetration probe placed within the dry good load item 3. Location of the dry good load item inside the autoclave chamber 4. Orientation of the dry good load item inside the autoclave chamber 5. Number of coils of the tubing elements of a dry good load item 6. Total thermal mass of the dry good load items placed inside the autoclave 7. Temperature of the dry good load items at the start of the sterilization cycle 8. Presence of residual moisture in the dry good load items at the start of sterilization cycle 9. Number of steam and vacuum pulses used for pre-conditioning in the autoclave recipe 10. Depth of steam and vacuum pulses used for pre-conditioning in the autoclave recipe 11. Hold time of steam and vacuum pulses used for pre-conditioning in the autoclave recipe The focus of this paper is on tests performed to evaluate these variables followed by analysis and interpretation of test data to identify key variables that have the highest impact on measurement of equilibration time. The conclusion of this paper presents a process to achieve shorter equilibration times in autoclaves through control of key variables identified.