Calibrating weighing and dosage equipment
16 June 2016
Properly functioning weighing and dosage equipment is extremely important in the pro-duction of feed. It is important to check frequently whether this equipment is still weigh-ing or dosing sufficiently accurate. This is called calibration (or gauge). When the scale or the dosage equipment deviates too much from an established standard, it must be ad-justed.
The GMP+ requirements
The GMP+ Feed Certification scheme (GMP+ FC scheme) defines requirements for the weighing and dosage equipment, including the frequent calibration of this equipment.
See paragraph 220.127.116.11 of the GMP+ B1 standard for instance, which dictates the following:
“All scales and dosage devices installations which are used in the production of feed must be appropriate for the range of weights or volumes to be weighed or dosed, and their accuracy must be checked regularly.
The dosage capacity must also be matched to the quantity of product to be disseminated.”
Paragraph 18.104.22.168, heading ‘Controlling monitoring and measurement installations’ dictates that:
“Installations which are used for the weighing/dosage of premixtures, feed additives and feed medicines must be calibrated at least twice a year according to a method established by the organisation and which achieves the objectives of the GMP+ FSA module.
All installations which are used for the dosing of - for example - feed materials must be calibrated at least once per year.”
Please note: The standard GMP+ B2 ‘Production of feed ingredients’, mainly defines requirements for calibration of equipment in similar wording in paragraph 22.214.171.124 and 5.3.2.
Many legislations require frequent calibration of scales used for trade purposes, such as the delivery of feed to livestock farmers.
In the context of the GMP+ FC scheme however, it mainly concerns the equipment used in the production. After all, incorrect dosage/weighing may lead to bad mixtures or exceedance of the limits defined for undesirable substances, medicines or additives. That is why this equipment must function properly and be suitable for carefully weighing or dosing the amounts. In this context, the equipment used to add processing aids, should be included as well.
A maintenance plan must be in place that ensures the permanent proper functioning of the equipment.