Depyrogenation Tunnel Validation

Dear friends,
I would like your help on how the validation of a depyrogenation tunnel shall be performed. I am familiar with the theoretical concept of the validation (i.e. empty chamber heat distribution, full chamber heat penetration, at least 3 log units reduction for BET concn. challenge test). What I would like to ask has to do with the process of validation.
Empty Tunnel: What I plan to do is to use 8 thermosensors placed on the same line and have them pass through the tunnel under the requested period of time and the set temperature. Is that enough?
Full Tunnel: I persume the tunnel must be loaded with the glass vials (selected as worst cases); the thermosensors inserted on 8 vials and have them again pass through the tunnel for the requested period of time. My question is, should the glass vials selected to carry the thermosensors be on the same line or theses glass vials should be selected randomly or based on a specific load schedule (although we are referring to a tunnel)?
Your help is very much appreciated, since I have to perform the validation tomorrow noon.

Best regards,

What type of thermosensors are you using? Typically tunnels run at a very high temperature and most stand alone sensors cannot withstand the heat. Traditional thermocouples have the issue of feeding into the tunnel and then the potential for them to move is present.

I think you have a good start, your first test will show uniformity across the belt and through the tunnel. You should be able to discern the belt location that is your worst case, empty by FH values.

For you full belt test, I wouldn’t randomly place the sensors but I would concentrate on the areas deemed most likely to have lowest FH value. Without knowing the tunnel configuration, could be the middle or one side. Also place one in the cold belt location from the empty chamber. Then you can make a comparison between empty chamber FH values and full chamber FH values.

You may want to change the belt speed based on these values, and determine your edge of failure. Once you have the belt speed, temperatures and worst case location, you can start performance testing. Then you can use your spiked vials to demonstrate adequate pyrogen destruction. I always run sensors with the pyrogen and calculate the FH too.

What about overkill parameters?

Dear Meyert thank you very much for your quick response.
In deed the thermosensors we are using have 6m length, therefore no problem on that.

The tunnel is a newly installed part of a newly installed line. The manufacturer has provided the set point for temperature but no other data such as belt speed, which we will have to identify with respect to remaining time in order to achieve the requested Fh value.

My concept if I understand well, is exactly as yours. The BET indicators (vials) shall be placed next to the vials carrying the thermocouples.

These trials are to be the definition of validation.

Again thank you very much.

[quote=Gigastorm]Dear Meyert thank you very much for your quick response.
In deed the thermosensors we are using have 6m length, therefore no problem on that.

The tunnel is a newly installed part of a newly installed line. The manufacturer has provided the set point for temperature but no other data such as belt speed, which we will have to identify with respect to remaining time in order to achieve the requested Fh value.

My concept if I understand well, is exactly as yours. The BET indicators (vials) shall be placed next to the vials carrying the thermocouples.

These trials are to be the definition of validation.

Again thank you very much.[/quote]

Dear Gigastorm,
First you have to know what is the filling line speed of different vials, means, the qualification of tunnel depend of vial dia size, belt width, hot zone belt length, set temperature, initially you have to determine the belt speed according to your filling line speed, by using formula you can easily determine belt speed at worst case then , at that speed you perform empty heat mapping study, then loaded the full belt iwth vials and perform distribution and penetration studies, and repeat dis/pentratio studies with 1000 EU/ml CSE. For over kill approach you can icrease the sterilization time in hot zone.

Thanks

Yes, I think you have it. Kaye makes a wireless temperature device and a thermal shield for tunnel applications. you may want to look at this for your next validation.

Thank you both for the clarifications.

Meyert, I used to work with Kaye in my previous company. I have just entered another pharmaceutical company but the have not been using this equipment. Therefore, I will have to proceed with the existing means.

Best regards,

[quote=Gigastorm]Thank you both for the clarifications.

Meyert, I used to work with Kaye in my previous company. I have just entered another pharmaceutical company but the have not been using this equipment. Therefore, I will have to proceed with the existing means.

Best regards,[/quote]

Dear Gigastrom,
If you still have any problem regarding tunnel qualification and validation of sterilization cycle then you can ask freely.

Thanks

Dear Forum,
What z-value and reference temperature value shall be used in calculating Fh for a depyrogenation cycle, using dry heat oven?

Regards,
:slight_smile:

[quote=Allerman]Dear Forum,
What z-value and reference temperature value shall be used in calculating Fh for a depyrogenation cycle, using dry heat oven?

Regards,
:)[/quote]

You can use 20°C and Tb is 170°C , or 250°C depends your cycle, you can select and develop 250°C for 30 minutes.

Thanks

[quote=Shahnawaz]You can use 20°C and Tb is 170°C , or 250°C depends your cycle, you can select and develop 250°C for 30 minutes.

Thanks[/quote]

Thanks Shahnawaz for your reply,
Just for my understanding, for a temperature of 250C, I would use a z-value of ?? to calculate the Fh (for a depyrogenation cycle)?

Best regards

20°C Z value and 250«C for 30 minutes cycle.

[quote=Allerman]Thanks Shahnawaz for your reply,
Just for my understanding, for a temperature of 250C, I would use a z-value of ?? to calculate the Fh (for a depyrogenation cycle)?

Best regards[/quote]

sir
when we are validate the tunnel set temp. is 320 degree for 2.8 minute maintane why

I am in the process of validating an oven for the depyrogenation process. what should be the reference temp and Z value that I need to use to determine Lethality. Is there a refernce for these valuse in any standards? I will be using 260C for two hours for the depyrogenation process.

Hi Dear Shahnawaz
Plz let me know regarding the calculation of 3 log reduction of endotoxins in case of tunnel validation. Can u help me buy providing a validation protocol in full detail.

Shazia
Assistant manager validation
fgh101020@yahoo.com

[quote=fgh101020]Hi Dear Shahnawaz
Plz let me know regarding the calculation of 3 log reduction of endotoxins in case of tunnel validation. Can u help me buy providing a validation protocol in full detail.

Shazia
Assistant manager validation
fgh101020@yahoo.com[/quote]

Hi dear Shazia,

I have sent you reply in your mail box.

Thanks and best regards

We are trying to shorten our oven depyrogenation cycle from 3 hrs dwell at 250C to 15 min dwell @255C. Before we through this in the dark I would like to know if there is a minimum temp and lenght or a graph for EI reduction available so we can calculate then procced?

Hello,

I am wondering as to the Z-values to use during verification of tunnel cooling zone sterilization.

I am currently using a reference temp of 170C and a Z value of 20, however our operating setpoint is 240, and I am calculating cumulative Fh(170) values in the 20,000 minutes range. Note this is for the sterilization of the cooling zone only.

Dear Forum members,

We are having the Sterilisation tunnels for both amp. and tunnel. We have perfomed the validation at 330ºC. Minimum 3min. is achieve. During FH calculation/SAL calculation, What reference temperature has to take. 250ºC or 170ºC. But supplier given the D value at 170ºC as 1.9 min. Is there any correlation graphy is there for 170 Vs 250 for finding the D value. Z value temp. what we have to take.

kanth

[quote=Shahnawaz]Hi dear Shazia,

I have sent you reply in your mail box.

Thanks and best regards[/quote]

Dear shahnawaz,

kindly send me the protocol and calculation.

thanks n regards
prashant
prashant4vedi@yahoo.co.in

@kanthachari,

Dear,

what process you want to validate? Usually, if you validate depyrogenation proces as worst case so there is no need for dry heat sterilization validation.

For depy process you need to have more than 3 log of EU (endotoxin unit) and Fd greater trhen 30.

Base values are 250oC and z=46.4oC.

So, no need for d values and 170oC