Sterilizing Tunnel Depyrogenation Test

Dear all, i have a question about sterilizing tunnel validation. When conduct the Depyrogenation Test, which Z value(54 or 46.4 ) should i take to calculate Fh value (take 250℃ as basic temperature)?
Is there any guidelines or standards to define the Z value?
Appreciate for your reply.

Dear Sir,

The Parenteral Drug Association mentions 170 °C / 54 °C and 250 °C / 46.4 °C. You may find these reports useful:
PDA TR# 3: Validation of Dry Heat Processes Used for Sterilization and Depyrogenation.
PDA TR# 7: Depyrogenation.

Especially, wireless transmitting data loggers may be convenient for the tunnel validation.

Best regards,

Enrique Riis

Dear Enrique Riis,
Can you tell me where I can find the above guide line PDA TR 3 and PDA TR 7. I do not have the ability to buy it.

Best regards


Dear Sujan,

You may be able to find excerpts from the reports on the internet. However, for full availability of the reports I suggest you go to

Best regards,