Validation FAQ

Validate FAQs

What is a validation

Within the framework of quality assurance, validation is to be divided into three stages: Installation Qualification (IQ), Functional Qualification (OQ) and Performance Qualification (PQ).
by Swiss Good Practice for the Reprocessing of Medical Devices

Installation Qualification (IQ)

– Testing of water/steam quality
– Testing of the sterilizer installation
– Structural and technical requirements
– Testing of the manufacturer's documentation
– Description of the programs
– Description of the process parameters and tolerances
– Description of the product family(s) that can be sterilized and their limitations with regard to size and/or weight
– Description of the reference load/sterilizer loading plan/list of instruments

Functional Qualification (OQ)

– Calibration of the system pressure/temperature
– Testing for air leaks: Checking the cycle parameters and the test
– Steam penetration test (B&D test): Checking the cycle parameters and the test
– Steam penetration test with hollow body systems (Process Challenge Device, PCD) according to SN EN 28
The IQ and OQ are each part of the installation of a new system.

Performance Qualification (PQ)

– Thermometric testing of a minimum load
– Thermometric testing of three reference loads per program
– Interpretation of physical parameters (time, temperature, pressure, theoretical temperatures)
– Assessment of the dryness of the reference load
– Visual inspection of the integrity of packaging and sterilized medical devices

What is a requalification

Following the detailed validation, requalification must be carried out annually. This consists of the following points:
by Swiss Good Practice for the Reprocessing of Medical Devices

Installation Qualification (IQ)
– Testing the quality of the water and steam condensate;

Functional Qualification (OQ)

– Calibration of the system; Pressure/Temperature
– Testing of the safety and fault detection systems
; Air leakage testing
; Steam penetration testing (B&D test)
; Steam penetration testing with hollow body systems (Process Challenge Device, PCD) according to SN EN 28.
We perform the IQ and OQ revalidation as part of our annual maintenance.

Performance Qualification (PQ)

– Thermometric testing of a minimum load
– Thermometric testing of a reference load per program
– Testing of the reproducibility and interpretation of the physical parameters (time, temperature, pressure, theoretical temperatures) in comparison to the previous validation
– Assessment of the dryness of the load
– Visual inspection of the integrity of the packaging and the sterilized goods

What is a steam quality test

Non-condensable gases (NCG) in the sterilizing steam such as air and/or CO2 can seriously jeopardize the efficiency of steam sterilization processes under certain conditions. These gases are found in steam for various reasons:

Drinking water fed into the steam generator or the upstream water treatment plant can contain significant amounts of dissolved air.
Storing (deionized) feed water in an open (ventilated) tank may lead to the dissolution of air and (primarily) CO2 until equilibrium with the atmosphere is reached.
Steam generation systems designed for general use (eg heating, kitchen, laundry) often produce steam of insufficient quality for sterilization.
The withdrawal of very different steam quantities over time together with the discontinuous feeding of the steam generator leads to strong fluctuations in the NCG.
Leaks in the door seal, lines or valves when a vacuum is present.
Residual air in the chamber if it was not sufficiently removed before sterilization.
With pneumatically operated door seals, if the seal is damaged, air can enter the chamber unnoticed through the seal. This source of danger for NCGs in the sterilization steam is naturally not present with seals that are operated with water or steam.
When the sterilizer is started up, there is usually still air in the steam generator, in the connecting lines and in the double jacket of the chamber that flowed in when the system cooled down. This air gets into the sterilization steam unless special measures (eg empty batch) are taken to remove the air.

Small quantities of NCGs in the steam are not critical for the respective process, as long as the steam or water can mix with the NCGs and this mixture reaches all surfaces to be sterilized. The quantities of NCGs that become critical depend on the goods. For example a 7kg Bowie Dick laundry package shows errors via inserted indicator sheet or the growth of inserted biological indicators. This way it can be detected if 150 -200 ml of air accumulated inside the package

Due to the high steam consumption when heating the sterilized items from room temperature to sterilization temperature, even though the concentration of NCGs in the steam is low, such quantities of NCGs accumulate that sterilization safety can be compromised. Therefore, the NCG content is an important quality characteristic of sterilizing steam.

The limit value for NCGs in DIN EN 285 of 3.5% is used to assess the performance of sterilization processes for standardized sterilization items. Tolerable NCG quantities in practice must be determined during process validation.