5 replies to this topic

[Fara Dieba]

Hi,

 

May I know is there any specified intervals for external calibration (analytical balance & incubator) ? 

 

Can I do it every 2 years because I use it only 2 / 3 times per month and we do internal calibration every month.

 

thanks in advance!

 

[Tony-C]

Hi Fara,

 

Normally external calibration is carried out at a frequency based on a risk.

 

 If the equipment/instrument is carrying out critical checks, such as for food safety, monitoring Critical Control Points or for product legality such as quantity/weight checks then an annual calibration may be required at a minimum.

 

You need to also consider your level of checks/monitoring, historical reliability and any manufacturer’s recommendations.

 

In your case, every 2 years may be acceptable if for example you check the balance with calibrated weights and the incubator temperature with a calibrated NPL thermometer and the calibration certificate you have doesn't have an expiry date.

 

Kind regards,

 

Tony

 

[Fara Dieba]

Hi Fara,

 

Normally external calibration is carried out at a frequency based on a risk.

 

 If the equipment/instrument is carrying out critical checks, such as for food safety, monitoring Critical Control Points or for product legality such as quantity/weight checks then an annual calibration may be required at a minimum.

 

You need to also consider your level of checks/monitoring, historical reliability and any manufacturer’s recommendations.

 

In your case, every 2 years may be acceptable if for example you check the balance with calibrated weights and the incubator temperature with a calibrated NPL thermometer and the calibration certificate you have doesn't have an expiry date.

 

Kind regards,

 

Tony

 

 

So it is acceptable if I use mercury thermometer(calibrated by 3rd party) and calibrate the laboratory incubator by myself? 

and I don't need to send my incubator to 3rd party for calibration right?

Edited by Fara Dieba, 09 August 2023 - 06:36 AM.

[Charles.C]

So it is acceptable if I use mercury thermometer(calibrated by 3rd party) and calibrate the laboratory incubator by myself? 

and I don't need to send my incubator to 3rd party for calibration right?

You will presumably also require an appropriate Procedure for calibrating the Incubator (eg temperature variations) and a thermometer externally calibrated at appropriate temperatures.

 

Why use a  mercury thermometer ? ( I daresay cheaper but I would have thought thermocouple more rapid responses and can be miniaturised/automated ).

[Fara Dieba]

You will presumably also require an appropriate Procedure for calibrating the Incubator (eg temperature variations) and a thermometer externally calibrated at appropriate temperatures.

 

Why use a  mercury thermometer ? ( I daresay cheaper but I would have thought thermocouple more rapid responses and can be miniaturised/automated ).

 

Mercury thermometer act as master when i calibrate the other thermometer. 

[Charles.C]

Mercury thermometer act as master when i calibrate the other thermometer. 

Thanks, that makes sense.

Note that if incubator running at say nominally 36degC, you may require the master/sub-master to have a specific calibration at that value. (The subsequent practical usage  depends on how the external calibrator quantitates/presents their results).