Direct answer
Under the UK average system, the batch average, tolerable negative error rules and individual pack limits must be controlled. The e-mark is voluntary and is a declaration that applicable average-system criteria are met; it is not simply a decorative packaging symbol. Obtain Trading Standards or specialist advice for the actual product and pack.
Practical objective: a documented quantity-control process that measures the right characteristic, uses suitable equipment and retains evidence.
Questions and phrases customers use
This guide also answers searches such as:
- average quantity system
- e mark packaged goods
- checkweigher legal metrology
- three packers rules
Information to collect first
Use one controlled set of figures and representative production conditions. Record the source and date of each assumption so quotations and improvement options can be compared on the same basis.
- Confirm whether packs are made to a constant nominal quantity and which legal regime applies
- Define nominal quantity and applicable tolerable negative error
- Choose gross-to-net, tare or direct net-content measurement appropriately
- Confirm weighing or measuring equipment is suitable and controlled
- Set sampling, batch definition and record retention
- Separate legal compliance control from commercial giveaway reduction
How to make the decision
Work from the required finished result back through the process. Keep compliance, product quality, sustained output and total ownership cost visible together.
- Use a capable filler to centre the process above the compliance boundary
- Use checkweighing or sampling that represents the batch and packaging tare variation
- Investigate trends before limits are breached
- Control recipes, calibration checks and rejected-pack handling
- Seek local Trading Standards advice where interpretation or equipment suitability is uncertain
Common mistakes to avoid
- Assuming average compliance means any individual underfill is acceptable
- Using average gross weight without controlling tare variation
- Applying the e-mark without meeting the applicable criteria
- Reducing overfill without checking process capability and legal limits
Customer decision table
| Control question | Evidence |
|---|---|
| Is the average adequate? | Batch or sample results using the approved method |
| Are too many packs below TNE? | Count and proportion against the relevant rules |
| Is any pack below twice TNE? | Individual pack measurement and rejection |
| Is equipment suitable? | Selection, checks, calibration or verification records |
Questions customers also ask
Is the e-mark compulsory in the UK?
Can a checkweigher prove net content automatically?
Can giveaway be reduced to zero?
How long should records be kept?
Official sources and further reading
Use the current source pages for legal, regulatory or scheme details. This guide is practical production planning, not legal or tax advice.
Download the planning template
Use the CSV worksheet to allocate evidence, owners, actions and dates before requesting quotations or approving a change.
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