Trouble with Equilibration Time

Understanding and analysis of Equilibration Time will tell, how your cycle is consistent. Recently an article in PDA journal (1) was published to understand the impact of the following autoclave variables on the consistent measurement of the equilibration time and on the reduction of the equilibration time.

Based on the all demonstrated study in the article, following recommendations are made,

Following point need to ensured,

Temperatures of the thermocouples that are placed in the test items are consistently maintained within the same temperature ranges during the start of the autoclave cycles in repeated tests.

Thermocouples are consistently placed in the same locations within the same test items used during repeated tests. Measure and fix a constant depth to which the Thermocouples are probed inside a specific test item during repeated tests.

Equilibration time is consistently measured using the same thermal mass within the autoclave with either maximum loading or minimum loading.

Moisture levels within the test items are consistently maintained within specific ranges across repeated tests. Maintain moisture levels as low as possible.

Locations of the test items within the autoclave chamber are identical across repeated tests.

Autoclave recipe is optimized to achieve low values of equilibration time by either increasing the number or the depth or both the number and the depth of the alternating steam and vacuum pulses used during the preconditioning phase of the autoclave cycle.

Once the autoclave recipe is optimized to achieve low values of equilibration time, add hold times to the alternating steam and vacuum pulses used during the preconditioning phase of the autoclave.

Recommendation: For more details please refer the article, details mentioned in the reference.

Reference:

Measurement of Equilibration Time of Dry Goods Loads in Autoclaves, Soham Shah, Sara Alayli and Yiming Peng , PDA J Pharm Sci and Tech 2019, 73 293-319