FAQ H_²O_² Sterilization

FAQ (Frequently Asked Questions) for H_²O_² -Sterilization for Freeze Dryers (Lyophilizers)

Can our freeze dryer be equipped with the VAPOVAC sterilizer?
New built freeze dryers are available having the VAPOVAC sterilizer incorporated.

Old existing freeze dryers which are not steam sterilizable can be retrofitted with the VAPOVAC sterilizer as well at a reasonable price and with reasonable effort. Therefore an expert of GEA-Lyophil will evaluate your freeze dryer on site to determine the neccessary changes.

Up to which freeze dryer volume can be sterilized ?
Up to 30 cubic meter freeze dryer volume.

How does the VAPOVAC sterilizer communicate with our freeze dryer ?
Dry contacts when retrofitted to older freeze dryers.
Bussystem when integrated in new built freeze dryers.

Except for the freeze dryer, can H_²O_²  sterilize the tanks or pipes?
Any vacuum vessel and associated piping can be sterilized. We only support the sterilization of freeze dryer at this time.

What freeze dryer conditions are required for the VAPOVAC sterilization ?
The freeze dryer must be defrosted and dry and at ambient temperature.

How can we remove residual moisture from our freeze dryer ?
Water droplets will be dried off by the drying phase of the VAPOVAC cycle.

What vacuum level is required for VAPOVAC sterilization ?
About 0,02 mbar before injection.

How long does a VAPOVAC sterilization take ?
An average cycle takes less than 3 hours total cycle time (basis: average production size freeze dryer).

• The better the vacuum pump set capacity,
• The dryer the freeze dryer vessels,
• The smaller the freeze dryer volume
• The smaller existing dead ends

the shorter is the sterilization cycle.

What is the H₂O₂ consumption during a VAPOVAC sterilization cycle ?
An average cycle takes total 25 to 100 ml H_²O_²  (basis: average production size freeze dryer).

• The smaller the freeze dryer volume
• The smaller existing dead ends

 the smaller the amount of H_²O_²  required for the VAPOVAC sterilization.

How do you protect the operator ?
The last action of the aeration phase is the H_²O_² -residual check. The MAK-level of 1ppm should not be exceeded before door opening is released. The operator can check the H_²O_² residual manually using an indicator tube and hand pump or the system can be equipped optionally with an automatic H_²O_² -residual-sensor.

What SAL (sterility assurance level) is possible with VAPOVAC sterilization ?
6 log reduction

Is there a difference in validation when changing from steam sterilization to H_²O_²   – sterilization?
No, the procedure is the same.  Chemical and biological indicators especially designed for vaporized hydrogen are required.

Can we sterilize the cold trap (condenser) as well?
The condenser and the chamber and associated piping will be sterilized.

How is validation performed ?
You pick the spots of assumed worst access for the gas to reach and place your biological indicators and run a validation cycle. This is exactly the same procedure as using steam only that you use biological indicators which are designed for H_²O_² -gas. The BI's are transferred and evaluated the same way in the laboratory as you would do with steam bioindicators.