Under national trade measurement legislation, manufacturers, packers, importers and sellers of pre-packaged goods must:
- ensure packages are correctly labelled; the laws include requirements for measurement marking and packer’s identification
- ensure packages they import, pack or sell include a measurement marking
- ensure the measurement marking is accurate and does not include the weight of any packaging material
- have appropriate measuring instruments: any measuring instruments used to perform compliance sampling must be suitable for the task, and properly maintained to ensure they remain accurate at all times
- assist trade measurement inspectors with any enquiries and provide information if required
Pre-packaged goods with common measurements
Manufacturers, packers and importers, can choose either of two methods for determining the measurement of pre-packaged goods with common measurements or ‘constant nominal content’.
The first method is the average system where:
- the average content in a sample of pre-packaged goods of the same kind and measurement cannot be less than the stated quantity marked on the packages
- no package can have a shortfall greater than 5% of the stated quantity
- the permissible average deficiency in a sample of 12 or more packages is nil (see exceptions below) – an inspector will generally check 12 packages but can choose a number of packages greater than 12 for this sampling process, depending on the circumstances
- a small number of ‘desiccating’ goods (that is goods, such as mushrooms and soap, that lose moisture after packing) are allowed a greater permissible maximum deficiency and an average deficiency after the day of packing to reflect this moisture loss. You should check the detail of the trade measurement laws for these desiccating goods and the measurement-marking requirements
The second method is the Average Quantity System (AQS). Under AQS, manufacturers, packers and importers, must comply with three important rules:
- the average net content in a sample from the production run of pre-packaged goods cannot be less than the stated quantity marked on the packages
- allowance is made for a small number of packages to exceed a ‘tolerable deficiency’
- none of the packages in the sample can have more than twice the prescribed tolerable deficiency
Find out more about the Average Quantity System.
Pre-packaged goods with differing measurements
These goods are known as random-weight or catch-weight packages. It is not possible to undertake a sample because while they are the same kind of product, the measurement differs. It is not meaningful to calculate an ‘average’ measurement.
The measurement of any such package – whether it is expressed as weight, volume, number, area or length – must not be less than the measurement stated on the package label. The legislation does not allow for any deficiency in even a single package’s contents.
The legislation does not allow a deficiency for ‘desiccating’ goods, other than pre-packaged fresh mushrooms or pre-packaged soap marked “mass when packed”. If the product is likely to lose weight over time through evaporation, dehydration or other means, the packer must make allowances for any expected losses in the measurement when packaging the product for the entirety of its shelf life.
All goods pre-packaged for sale must be marked with the net measurement (i.e. the weight of the contents without the packaging material).
Unit price marking for retail sale
Many pre-packaged goods which are sold by weight (especially foods such as fruit, vegetables, cheese, meat, fish and smallgoods) are sold by unit price that is price per kilogram. These pre-packaged goods should be marked in the required manner with the weight, price per kilogram and total price for the article.
Sale by number or linear or area measurement
Certain products do not have to be sold by weights or volume when pre-packaged, but can be sold by number or linear or area measurement. You can find a list of these products at Approval for the sale of products by number or linear or area measurement.