Interpretation of Validation/Verification
There is much confusion about the meaning and use of these terms when applied to food safety management. They are often used interchangeably to describe the same function or activity. Global Standards and codes of practice use them with an assumption that the user already has a clear understanding of their meaning – which is not always the case. I have also experienced third party auditors who displayed a poor understanding of the two terms (although less so in recent years).
I must admit I am also a veteran of the mental twists and turns required to pin-down exactly what Verification and Validation mean when applied to quality and food safety. To gain a clear insight it is helpful to apply them to a real food safety scenario…
Let’s take, for example, the following:
- A food company producing a cooked meat product.
- Their Hazard Analysis has identified Salmonella spp. as a hazard.
- The company cooks the meat to a minimum temperature of 70oC for a minimum 2 minutes.
- This is a CCP and is applied to reduce the risk to an acceptable level.
The company now sets up a monitoring plan to check the core temperature of the meat every 10 minutes during the cooking process using a temperature probe. It is the Cooker Operator’s responsibility to check and record the temperature / time is to specification.
Now applied to the above we may define Verification and Validation as follows:
VERIFICATION: This is the action of checking that what we say we are doing – we are in fact doing! i.e. the operator is checking the temperature / time every 10 minutes according to the HACCP plan and recording the result. We are simply ‘verifying’ that the requirements of the plan are being met.
VALIDATION: This is confirming (or proving) that what we are doing is in fact capable of reducing the hazard to an acceptable level. In other words ‘Is cooking the meat to 70oC for 2 minutes sufficient to kill Salmonella?’
So we are answering two separate questions:
- Are we doing what we say? (Verification) and
- Is what we’re doing adequate? (Validation).
Verification activities include sign-off of records by a Supervisor/Manager, internal auditing, calibration etc.
Validation activities include challenge testing, shelf-life testing, reference to reputable standards, research papers, legislation, codes of practice etc.
The above, from my experience, is a good example and is generally accepted by auditors – I hope it provides some clarification.