When is it unlawful to make changes to the recorded weight on a weigh master certificate?

The correct answer is based on the understanding that once the tare weight has been recorded on a weigh master certificate, it is essential to maintain the integrity of the documentation, as tampering or altering this information can lead to legal consequences and inaccurate weight assessments.

The tare weight is critical because it represents the weight of the container or packaging that holds the commodity being measured, thereby ensuring that only the weight of the product itself is considered in subsequent measurements. If changes to the tare weight are made, it compromises the validity of the entire weight calculation process—particularly affecting the net weight and total weight.

Maintaining accurate tare weight records is crucial for compliance with regulations governing weight verification, thereby safeguarding fair trading practices and preventing potential fraud. Therefore, alterations to this recorded tare weight are never permissible, making this option the correct choice.