MICLAB-025 Depyrogenation of Glassware in Microbiology Laboratory Oven

1. Preparation of Glassware for Depyrogenation

1.1.         Depyrogenation oven has an approximate loading capacity of 168 liters with 4 loading levels as indicated in Picture A.

1.2.         Loading (as per Picture D)

Test Tubes – Double Wrap with an Aluminium foil (maximum of 6 test tubes per packet).  Can be loaded up to 12 packets (72 test tubes)

100ml vials – Load on to 430mx275mmx95mm covered stainless steel boxes: 40 (=5×8) vials upside down.  Can be loaded up to 2 stainless steel boxes: (80 vials).

(Note: Total of 7 Paraffin Oil bottles can be loaded in addition to the Load indicated in Section 1.2.  Paraffin Oil bottles can be loaded on any level (from 1 to 4), i.e. there is no need to load all items mentioned in Section 1.2 in one cycle.)

1.3.         A Thermax D dry heat indicator 5L series (160‑199 range) is to be included (Picture E) in each parcel either stuck to foil pack or attached to a piece of foil and placed inside the tin.

2. Depyrogenation of Glassware

2.1.         The prepared equipment is placed in the oven allowing sufficient room for air to circulate freely around it.  Close the door and fasten the clamp.

2.2.         Set the control panel as indicated in Picture B (Range selector ‑ set at 200 Thermostat set at 100)

2.3.         Electronic circuit timer switch (Picture C) has been set to give six (6) hours of power.  To start the Depyrogenation oven, press the GREEN button.

This starts the 6-hour timer and switches the heater on.  The heater stays on until the 6 hours have been completed.  If required the timer and heater can be stopped/turned off by pressing the RED button.

2.4.         Once the depyrogenation cycle is completed, the electronic circuit timer resets the program; therefore there is no need to switch the oven or the timer off.

2.5.         Before using any of the depyrogenated glassware check that the Thermax dry heat indicator has changed colour and that a temperature of 182ºC has been reached on the Indicator.

2.6.         The entire depyrogenation cycle should be available to view and print.

3. Preparation of Paraffin Oil

Paraffin oil is used when conducting biochemical tests and as sterility controls when conducting direct inoculations.

3.1.         Half fill clean 100mL bottles full of Paraffin Oil.

3.2.         Cover the opening of the bottles with alfoil.  The lids for the bottles are to be bagged and autoclaved for 20 minutes at 121ºC.

3.3.         Place the bottles in the Depyrogenation Oven and follow steps 2.2 to 2.6.

3.4.         After the cycle is completed, exchange the alfoil for the autoclaved lids.  This should be done under the laminar flow using aseptic technique.

3.5.         Paraffin oil is given a 12 month expiry date from the date of depyrogenation.

4. Pictures of Depyrogenation oven, loading, Control Panel, etc

4.1.         Picture A (Empty Depyrogenation oven)

4.2.         Picture B (Control Panel)

4.3.         Picture C (Cycle On/Off Switch)

4.4.         Picture D (Loaded Depyrogenation oven)

4.5. Picture E (Thermax Indicators)

5. Summary of Changes