Internal Auditing

Internal audits are a valuable tool to assess the effectiveness of your Good Manufacturing Practices (GMPs), Hazard Analysis Critical Control Point (HACCP) or any other food safety system. They help you identify the strengths and weaknesses of your food safety system, and discover areas for improvement before an external audit occurs. Thus, you can implement corrective actions and prevent reoccurrences. Internal audits need to be more strict and rigorous than external audits and management commitment is essential to ensure the audits are conducted regularly and remain effective.

Audit frequency

The frequency of internal audits depends on each plant and process. You can conduct an initial internal audit of your entire system a few months after you implement your GMPs/HACCP system. This will help you assess your progress in implementing your food safety system. You need to allow sufficient time to generate records, identify deficiencies, take corrective actions and address problems and non-conformances.

At a minimum, you need to conduct a complete internal audit annually. Because the process is time consuming, you can split it into activities, areas or departments and spread them out over the entire year. For example, audit shipping one month and packaging the next month. A regular schedule may help you outline when to conduct the audits. Recurrent deviations and changes in your food safety system may require you to schedule an internal audit. Always conduct an internal audit before you apply for a certification/recognition audit.

Internal auditing steps:

Select audit team

Audit teams can have one, two or more people. Team size depends on the size of your facility and the complexity of your operation. Having people from different departments avoids focusing on specific areas, broadens expertise and avoids conflict of interests.

Auditor qualifications

When choosing internal auditors, consider the following:

Knowledge and skills:

  • familiarity with the facility requirements being evaluated
  • knowledge of the particular product, process, resources, inputs and outputs
  • ability to interpret and find evidence supporting how requirements are met
  • basic knowledge of audit procedures
  • previous experience in auditing (asset)
  • good writing skills

Personal traits:

  • good interpersonal skills (verbal and listening skills)
  • objective
  • detail oriented
  • observant
  • organized
  • analytical
  • patient

Conflict of Interest

To ensure internal audits are as unbiased as possible, the person who audits a process should not be involved in the related areas, departments or activities. Auditors must be impartial and objective and should have no interests in the process audited (ex: employees’ relationships, financial interests, audit own work, audit self developed procedures).

Prepare audit checklist

The audit checklist is a tool used to document your audit findings and notes. It provides the basis for the internal audit and corrective action report. The auditor needs to prepare this checklist. A blank external audit checklist may be used as your internal audit checklist. The internal audit checklist is specific to each facility.  Ensure your checklist is kept up to date.

In your checklist, include the requirements on what to look at and leave space for notes, findings and recommendations. The requirements can be worded using statements or series of open-ended questions to evaluate the degree of compliance.

Conduct the audit

Internal audits have two main components: documentation review (systems audit) and on-site audit (verification audit).

Documentation review

Consists of assessing documents for completeness. Check that all the GMPs/HACCP requirements are addressed.

For GMPs, evaluate all components including sourcing and delivery of ingredients, packaging materials, shipping and receiving, etc, by answering questions such as:

  • Is there a written program?
  • Are there written policies and procedures?
  • Are there written monitoring and corrective action procedures? Is the documentation complete and accurate and does it conform with the requirements?
  • Are there appropriate record keeping forms?

For HACCP, review all existing HACCP plans and their supporting protocols and documents by answering questions such as:

  • Is there a written HACCP plan?
  • Is the HACCP plan complete and does it cover all products and processes?
  • Is the HACCP plan supporting documentation available?
  • Is each Critical Control Point (CCP) effectively controlling the hazard?

On-site observations and interviews

After reviewing the documentation, check that programs, policies and procedures are implemented as written. Ensure they are current and reflect the operation. Review records for completeness and accuracy.

Visually assess elements such as: employee’s activities, personnel practices, design, conditions and maintenance of the internal structures (ex: floors, walls, ceiling and light fixtures), food contact surfaces, equipment, etc.

In a GMPs on-site audit, assess compliance by answering questions such as:

  • Does the written program reflect current operations?
  • Are the program and activities effective in preventing and controlling food safety hazards?
  • Are programs, policies and procedures being followed as written?
  • Are monitoring procedures being followed at the appropriate frequency?
  • Are there records of monitoring activities?
  • Are corrective actions taken when a deviation is identified?
  • Are corrective actions effective and documented in records?
  • Are employees trained to perform the activity?

In a HACCP on-site audit, evaluate if the HACCP plan and its supporting documentation are suitable and accurate by answering additional questions such as:

  • Are CCPs monitored at the appropriate frequency?
  • Are employees responsible for monitoring CCPs trained and do they comply with the written program?

During the on-site audit, the auditor needs to interview employees to evaluate their knowledge of food safety and GMPs/HACCP systems. Ask them about the activities they perform and the monitoring procedures they follow. For example:

  • What was the last corrective action taken?
  • Show me where you document the monitoring activities
  • Explain what you are doing.
  • How do you know the thermometer is reading the correct temperature?
  • What is the critical limit?
  • What happens if you cut yourself while handling food products?
  • Show me how you wash your hands.

Use open-ended questions over close-ended questions to avoid yes/no answers and encourage full, meaningful answers. For example:

Close-ended questions Open-ended questions (Recommended)
Do you know the procedure? What is the procedure to follow?
Do you take corrective actions when there is a deviation? What are the corrective actions to take in case of deviation?
Do you monitor everyday? How often do you monitor?


Avoid interfering with the plant operation while interviewing employees. Conduct the interviews in a non-threatening manner, and avoid criticizing so employees feel free to answer truthfully. Explain why you are asking questions and describe how the outcome of the internal audit may help lead to improvements. You may also start by complimenting employees’ work area or individual performance.

Observing employees activities and interviewing them helps you gather sufficient information to make accurate assessments.

Prepare the audit report

After conducting the audit, prepare a written report describing all relevant findings, observations, trends, areas for improvement and specific follow-up issues. The audit report needs to be accurate, clear and unbiased. It needs to identify system deficiencies and not individuals. Focus on findings that have an impact on food safety.

Write the report in a language, style and structure that is easy to understand. Try to be consistent with the presentation of the internal audit report. You may use your blank checklist as the audit report form.

Internal audit follow-up

The audited areas need to develop corrective action plans for all non-conformances, areas of improvement and trends identified during the audit and, set timelines for their implementation. Make sure corrective actions taken are documented.

One of the most important parts of internal audits is the follow-up. Auditors need to review the evidence that corrective actions were taken and assess their effectiveness.

Auditors must evaluate the adequacy of the corrective actions in the next internal audit. You may include the additional items you need to look at to your original checklist.

Internal audit results and follow-up activities need to be a priority. Regardless of the size of the facility, internal audits are key to continuous improvement of your food safety systems.

For more information, email the Food Safety and Inspection Branch or call 204-795-8418 in Winnipeg.