Desiccating goods defences
Selling short quantity packages is an offence under the Weights and Measures Act, but the Act does offer a possible defence in the case of desiccating goods.
About the defences
Some goods that have been packaged to a stated net quantity may lose weight or volume over time as a result of moisture loss.
The Weights and Measures Act (the Act) provides a defence in the case of a package containing desiccating goods. The defence applies if it can be proven that at any time on the day the goods were packed, or at any time within a 7 day period of being packed, the goods met all 3 requirements of the Average Quantity System (AQS).
There is a further defence if it can be proven that after the 7 day period there are no inadequate packages in the sample (third requirement in the AQS).
These defences are only available for goods that desiccate. Trading Standards Officers may need to seek an expert opinion as to whether the goods are of a type that can be classed as desiccating.
Some words have specific meanings in the context of desiccating good defences. It's worth becoming familiar with these before reading about the defences.
See Desiccating goods terminology for more information.
Using the defences
Where goods are deemed to be desiccating, the Act provides two defences, Section 16A(4) and Section 16A(5) of the Act. To utilise either of these defences, the packer of those goods must prove evidence that their goods meet the conditions of the defence.
The desiccating goods defence can only be applied to goods which are of the same kind and packaged to a predetermined constant quantity. It can't be applied to goods packaged at varying quantities, referred to as 'catch weight goods'.
Defence 1 — Section 16A(4)
A person charged with an offence against this section, in respect of a package from a lot of packages containing desiccating goods, has a defence if they can prove that their goods meet ALL of the following rules within the required period (the 7 day period from the date the package was made up).
At all times during the required period, the weighted average quantity of any sample taken from the lot of packages — as determined in accordance with regulations made under section 41A — was equal to or exceeded the quantity stated on the package or a label attached to it.
At all times during the required period, the number of non-standard packages in any sample taken from the lot of packages was equal to or less than the appropriate number specified for the purpose in regulations made under section 41A.
There were no inadequate packages, at any time during the required period, in any sample taken from the lot of packages.
Defence 2 — Section 16A(5)
A person charged with an offence against this section in respect of a lot of packages containing desiccating goods also has a defence if they can prove that, at any time after the close of the required period, a sample taken from the lot contained no inadequate packages.
See General quantity labelling requirements for more information.
In order to demonstrate compliance using Defence 1, you'll need to prove that a sample of your goods meets all 3 rules of the Average Quantity System (AQS) stated above at all times within the required period. The AQS is the sampling methodology used by Trading Standards to assess whether a batch or lot is compliant, by assessing a statistical sample of that batch or lot.
If you'd like a copy of our spreadsheet, which you can use to determine whether a batch complies with the Act, contact your nearest Trading Standards office.
Packaged net quantity tolerances
Packaged net quantity tolerances are specified in Table 1 and Table 2 below.
Table 1 — Lots and sampling characteristics
|Number of packages in the lot of packages||Minimum sample size||Sample correction factor (c)||Number of non-standard packages permitted in a sample|
|More than 4,000||80||0.295||6|
Table 2 — Amount of error for packages labelled by mass or volume
|Stated quantity (g or ml or cm3)||Amount of error (% of stated quantity)||Amount of error (g or ml or cm3)|
|More than 0 to not more than 50||9.0||–|
|More than 50 to not more than 100||–||4.5|
|More than 100 to not more than 200||4.5||–|
|More than 200 to not more than 300||–||9.0|
|More than 300 to not more than 500||3.0||–|
|More than 500 to not more than 1,000||–||15.0|
|More than 1,000 to not more than 10,000||1.5||–|
|More than 10,000 to not more than 15,000||–||150.0|
|More than 15,000||1.0||–|
For the purposes of this table, if the quantity is stated in units other than grams, millilitres, or cubic centimetres, the quantity must be converted into the equivalent number of grams, millilitres, or cubic centimetres, as appropriate.
For example, if the quantity is stated in kilograms, litres, or cubic metres, the quantity must be converted into the equivalent number of grams, millilitres, or cubic centimetres, respectively. The table must then be applied accordingly.