Quality Assurance Guide—Application: Average System of Net Quantity Determination


March 1996

Table of contents


The Fair Business Practices mission helps ensure fair and effective market operations. This is essential for our mandate, which is to encourage a strong and competitive national market.

The Fair Business Practices Branch is responsible for the:

Consumer Packaging and Labelling Act, Textile Labelling Act, and Precious Metals Marking Act.

The Fair Business Practices Branch fulfils its mandate through the following three activities:

Compliance monitoring (voluntary and mandatory programs)
Policy development
Information and advice.

This document covers compliance and information activities in relation to the Consumer Packaging and Labelling Act and Regulations. We hope that manufacturers will find it a useful part of their quality assurance programs.


This guide is intended for all manufacturing companies concerned with minimizing the possibility of errors in the area of net quantity declaration. This quality assurance oriented document was prepared by the Consumer Products Directorate after consultation with interested companies. Although this guide is not a legal document, it sets out the principles and practices acceptable to the Fair Business Practices Branch. The goal of this guide is to help companies in minimizing the possiblity of errors in their products regarding the Consumer Packaging and Labelling Act and Regulations, and more specifically with The Average System of Net Quantity Determination. However, following this guide does not in any way guarantee compliance to the said Act and Regulations.

A company wishing to follow this guide will have to establish and maintain a quality system allowing it to ensure that prepackaged consumer products comply with the Consumer Packaging and Labelling Act and Regulations. This system should include:

  1. preparation of documented procedures and instructions relating to the quality system in accordance with the requirements set out in this program;
  2. effective implementation of these documented procedures and instructions

Companies which already have a quality assurance system in place need only incorporate the requirements described in the present guide into their own system. It is not necessary to set up a separate quality assurance system for net quantity.

Although it is unlikely that many changes will be made, this guide should not be viewed as a static document. It will be completed or modified from time to time, as needed, to reflect changes in regulations.

Advantages of quality assurance

Quality assurance aims above all at preventing nonconformity. It allows the company to promptly detect cases of non‑compliance, correct them and prevent their recurrence.

As the company's employees acquire more quality awareness and responsibility, the deviations detected at procedure control points will be dealt with rapidly and effectively. Not only will minor problems be readily corrected, but better monitoring will reduce the volume of products withdrawn or destroyed because they fail to meet standards. This will have a direct and positive effect on the firm and its customers.


This document is intended for all manufacturing companies interested in the application of quality assurance concepts as a means of controlling the declaration of net quantity as required by the Consumer Packaging and Labelling Act and Regulations. Interested companies are asked to refer to the said Act and Regulations and to the Average System of Net Quantity Determination for more details regarding legal requirements. While the present document focuses on net quantity verification, companies are reminded that there exist several other requirements in the Consumer Packaging and Labelling Act and Regulations. Companies may also wish to refer to Principles and Guidelines for Environmental Labelling and Advertising. As well, certain consumer products may also be subjected to other acts and regulations. Companies should contact the appropriate government departments for more information.

Control elements

In order to help companies implement a quality assurance system, this program specifies the elements to be followed in order to ensure compliance to the net quantity requirements of the Consumer Packaging and Labelling Act and Regulations. They are the following:

  1. Management commitment
  2. Organization
  3. Procedure control, monitoring, and testing
  4. Measuring equipment control (calibration)
  5. Non‑complying product and equipment control
  6. Quality records
  7. Document control
  8. Finished product traceability
  9. Internal audits
  10. Training
  11. System review

The requirements to be met in each control element will be described in the next pages.

1. Management commitment

Regardless of whether or not a company decides to follow this guide, it is legally responsible for the compliance of its products to the Consumer Packaging and Labelling Act and Regulations.

Over and above the legal requirements, to apply this approach, the company management must be committed to ensuring that the requirements set out in this guide are implemented and maintained at all applicable levels of the organization.

2. Organization

Management representative: The firm shall appoint a management representative who, irrespective of other responsibilities, shall have defined authority and responsibility for ensuring that the quality assurance system requirements are implemented on a permanent basis.

Organization chart (or other): Using a management organization chart (or other tool), the company should illustrate how the quality assurance system fits into the plant organization and how the program's principles, directives and strategies are applied in daily activities. There should be an indication of the links between the person in charge of quality assurance, the production managers, and other persons involved.

Responsibilities and authority: The responsibility, authority and interrelation of all personnel who manage, perform and verify work in relation to the system requirements shall be defined, particularly for personnel who need the organizational freedom and authority to:

  1. initiate action to prevent the occurrence of product nonconformity;
  2. identify and record any product quality problems;
  3. elicit, recommend or provide solution;
  4. verify the implementation of solutions;
  5. control further processing of a nonconforming product until the deficiency or unsatisfactory situation has been corrected.

3. Process control, inspection and testing

3.1 Process control

The firm shall describe the production procedures directly affecting net quantity and ensure that these procedures are performed in controlled conditions. The flow sheet should have enough details to be useful for spotting potential difficulties, but not be overloaded with minor details.

It should contain but not necessarily be limited to:

  1. sequence of operations
  2. equipment type
  3. work environment
  4. procedure control points and monitoring methods used at these control points
  5. name(s) of person(s) in charge of operations
  6. documentation to be used
  7. data recording methods
  8. acceptance numbers
  9. description of corrective action to be taken in cases of nonconformity

3.2 Inspection and testing

Inspection and testing during production permits identification of causes of nonconformity before the final control stage and increases overall activity effectiveness by preventing continued production of non‑complying products.

The company shall document the working procedures and instructions enabling it to meet the requirements set out in The Average System of Net Quantity Determination. In short, the requirements stipulate that a product batch must contain the declared quantity (section 7 of the Consumer Packaging and Labelling Act). The weighted sample average is used (see part II, Average System) to determine whether the lot average meets the requirements. Although some packages may deviate from the standard by more than the tolerance, their number is limited in relation to the sample size (see part IV, Average System). The parameters specified in the company's working instructions shall be established in relation to legislation, and procedures' reliability and capacity.

The parameters should include but not necessarily be limited to:

  1. equipment used
  2. equipment checks to be performed
  3. number of weighings
  4. place of sampling
  5. frequency of weighings
  6. acceptance numbers (tolerance, average)
  7. name(s) of person(s) in charge
  8. description of corrective action to be taken in cases of non‑compliance
  9. data recording methods
  10. density of checked product (for liquids)

For determining the density (if applicable), the parameters should include but not necessarily be limited to:

  1. equipment used
  2. equipment checks to be conducted
  3. environmental conditions (i.e. temperatures)
  4. number of tests
  5. place of sampling
  6. frequency of tests
  7. acceptance numbers
  8. name(s) of person(s) in charge
  9. data recording methods
  10. availability of certificates of analysis

The working procedures and instructions shall be approved by the designated person in charge.

The company must keep data records for the actions performed.

The minimum retention period for records and all certificates of analysis is three years.

4. Measuring equipment control

The firm shall make a list of all the measuring equipment (including control standards) used for net quantity checks and provide information identifying the equipment, such as: serial (or identification) number, equipment name, manufacturer, model, purchase/discard date, location, range of data reading, units of measure, precision, permitted limit of error.

The company shall also calibrate and adjust all measuring equipment affecting the net weight. Adjustments must be done in reference to equipment and/or standards which are themselves adjusted and certified.

The company's calibration procedures shall be documented. The parameters should include, but not necessarily be limited to:

  1. type of equipment
  2. frequency of verifications
  3. work environment
  4. acceptance numbers (precision)
  5. documentation to be used
  6. name(s) of the person(s) in charge
  7. data recording methods
  8. description of corrective action to be taken for nonconforming equipment
  9. availability of calibration records
  10. manner of indicating calibration on the equipment (marking)

The working procedures and instruction shall be approved by the designated person in charge.

The company shall keep data records for measurements performed.

The minimum retention period for records and all certificates of calibration is three years.

5. Control of non‑conforming product and equipment

The company shall establish and maintain procedures to ensure that products and equipment that do not comply to specified requirements are prevented from inadvertent use or installation. Control shall provide for identification, documentation, evaluation, segregation (when practical) and disposition of nonconforming product or equipment and for notification to the functions concerned.

The responsibility for review and authority for the disposition of the nonconforming product and equipment shall be defined.

The nonconforming product or equipment shall be inspected with documented procedures. It may be:

  1. reworked to meet the specified requirements,
  2. rejected or discarded, or
  3. re‑graded or re‑labelled.

Repaired and reworked product and equipment shall be re‑inspected in accordance with documented procedures.

For each case of nonconformity, the company shall have a record of the action that was taken ; this record shall provide the following information:

  1. a description of the nonconforming item
  2. lot number (or other means of identification)
  3. date of corrective action
  4. result
  5. signature of the person in charge.

6. Quality records

The company shall establish and maintain procedures for the identification, collection, indexing, filing, storage, maintenance and disposition of quality records.

Quality records shall be maintained to demonstrate achievement of the required quality and the effective operation of the quality system.

All quality records shall be legible and identifiable to the product involved. They shall be stored in a suitable environment and maintained in such a way that they are readily retrievable.

The minimum record retention period is three years.

7. Document control

7.1. Document approval and issue

The company shall establish and maintain procedures to control all documents and data that relate to the quality assurance program. Before being circulated, the documents shall be reviewed and approved for adequacy by authorized personnel prior to issue. This control shall ensure that:

  1. the pertinent issues of appropriate documents are available at all locations where operations essential to the effective functioning of the quality system are performed;
  2. obsolete documents are promptly removed from all points of issue or use.

7.2. Document changes/modifications

Changes to documents shall be reviewed and approved by the same persons who performed the original review and approval unless specifically designated otherwise. The designated persons shall have access to pertinent background information upon which to base their review and approval.

When possible, the nature of the change shall be identified in the document or the appropriate annexes.

A master list or equivalent document control procedure shall be established to identify the current revision of documents in order to prevent the use of non‑applicable documents.

The documents shall be re‑issued after modifications have been made.

8. Finished product traceability

The company shall develop a system allowing it to identify the lot to which each product belongs.

The company shall explain the product coding system in a document. The code used may be the production date or another code established by the company

9. Internal audits

The company shall carry out a comprehensive system of planned and documented internal audits in order to verify that the activities relating to the quality assurance system comply with the measures defined and to evaluate the effectiveness of the quality system.

The audits and their follow‑up shall be conducted according to an audit plan, including:

  1. audit objectives
  2. audit elements
  3. reference documents to be used
  4. names of auditors
  5. audit date

The audit results shall be recorded and provided to the persons in charge of the audited sector. The persons in charge of this sector shall apply corrective action in due time to remedy the deficiencies found during the audit.

10. Training

The company shall establish and maintain procedures for identifying the training needs of all employees responsible for an activity relating to the quality system. The persons responsible for performing specific tasks must be qualified through initial training, additional training and/or appropriate experience, as required. Inadequate staff training or lack of understanding of the importance of controlled production are often the reasons for non‑compliance of products to required standards. Appropriate training records shall be permanently maintained.

1) The training should cover, as applicable:

  1. For net quantity:
    1. auditing staff assigned to auditing weighing tasks
    2. quality department staff on the production floor
    3. packaging and production equipment operators
    4. laboratory staff (if applicable)
    5. other employees assigned to relieve or replace one of these positions.
  2. For auditing:
    1. staff responsible for quality system follow‑up
    2. staff responsible for the internal audit
  3. For quality assurance concepts:
    1. company staff

2) Training elements:

  1. Knowledge of the Average System of Net Quantity Determination
  2. Knowledge of the company's working procedures and instructions
  3. Knowledge of operation of scales and other measuring instruments
  4. Knowledge of production and/or packaging operations which can affect net quantity
  5. Knowledge of the Consumer Packaging and Labelling Act and Regulations
  6. Knowledge of quality audit procedures and practices
  7. Knowledge of quality assurance concepts

11. System review

The quality system adopted by the firm shall be reviewed at suitable intervals by company management in order to ensure that it is always appropriate and effective. The system should also be updated in accordance to changes in Consumer Packaging and Labelling Act and Regulations. Records of these reviews must be maintained.


The Average System of Net Quantity Determination, May 1995.
Source: Consumer Products Directorate (Industry Canada).

Consolidation of the Consumer Packaging and Labelling Act and Regulations, June 1996.
Source: Fair Business Practices Branch (Industry Canada).

The present guide is available in English and in French.

For more detailed information please contact the Information Centre of the Competition Bureau.

Online: Enquiries/Complaints