Desiccating goods (products that lose weight due to evaporation)
Some goods that are packaged to a stated net quantity may lose weight or volume over time through moisture loss. In some cases these may be considered to be 'desiccating goods'.
What are desiccating goods
The Weights and Measures Act 1987 (the Act) defines desiccating goods as "...any goods made up in a package that lose weight or volume solely through evaporation when the package is made up”. This loss of net quantity can occur when the goods are stored under environmental conditions that allow moisture to escape from the package.
Trading Standards will consider and decide if a particular type of good is desiccating on a case-by-case basis.
Offence to sell short quantity packaged goods
It's an offence if the weight, measure or number of goods in the package is less than that stated on the package or label.
If your goods are determined by a Trading Standards Officer to be short of their stated net quantity, you can refer to the desiccating goods defences to see whether they apply.
If these defences don't apply, you may be subject to enforcement action. The penalty for this offence is a fine not exceeding $10,000 on prosecution, or a $500 Infringement Offence fee.
Your packing system
Weight loss checks, especially with products known for moisture loss, should be completed as part of a packer's due diligence. When setting up a packing system, you should:
- Fill packages then set them aside for 7 days in normal storage conditions.
- Re-check the packages after 7 days to determine the amount of weight loss due to evaporation/settling.
- Add the deficient amount to the target fill weight.
- Repeat this process until you're confident that the packages will remain within the permitted tolerances for 7 days.
Importing goods from Australia
Under the Trans-Tasman Mutual Recognition Arrangement, any manufactured good that can be legally sold in Australia can be legally sold in New Zealand, and vice versa.
As a result of this agreement, there is an increased allowable deficiency for some prescribed items that have been imported into New Zealand from Australia — for example, soap and mushrooms. This is due to the goods being classed as 'desiccating goods' under Australian legislation.
In Australia, products that comply with the Average Quantity System are marked with the ‘e’ mark.
See the Australian Government's Guide to the Sale of Pre-packaged Goods(external link)for more information.