In-plant quality-testing laboratories often serve two discreet but related quality functions for any manufacturing process: they both focus on risk — but from different ends. One function, quality control (QC), is defined as a set of activities designed to evaluate risks of the product being manufactured. The other, quality assurance (QA), can be thought of as risk mitigation through quality management activities intended to ensure that the established processes are adequate to meet intended objectives. So, simply put, one looks at the risk of error in the product under manufacture while the other looks at the risk of error in the management of the quality process. Another way to look at it would be to think of QA as preventing and detecting quality problems, and QC as detecting errors in the product.
Collectively, QA and QC work to reduce the risk of a nonconforming outcome, and each works to help ensure that the quality requirements of the organization are met; that is, ensuring quality in the product, process, or service leading to a well-run manufacturing floor or laboratory bench. Looking at it this way, it seems fairly obvious that these QA/QC tools are part of a universal risk reduction toolkit since all products, processes, and services have to be able to meet someone’s material specifications.
For QA in the plant, a laboratory located in the manufacturing facility (in-plant lab) is primarily looking at whether there is a risk that the product, as tested, does not meet the requirements of either the regulator or an internal or external customer (or both). This is an activity of primary focus for A2LA when accrediting testing laboratories using the ISO/IEC 17025 General Requirements for the Competence of Testing and Calibration Laboratories. (It is sometimes also applied to the accreditation of QC activities.) This accreditation standard is used throughout the world as a tool for helping facilitate trade in the marketplace because vendors and customers both need assurance that there is a low risk that manufactured products do not meet quality specifications, including those related to purity, uniformity, and stability.
QC in the facility or the in-plant lab is a tool used to demonstrate or evaluate the validity of the manufacturing or testing process, and from that outcome, QC acts to provide positive feedback to the persons performing the task. For manufactured foods, this could include checks on physical characteristics such as product size, shape, weight, volume, count per package, presence of fines, or any other specific defining features of the particular food. Proximate analysis covers basic chemical characteristics along with checks on ingredients used to chemically define food products. Chemical reference standards are necessary in nutritional labeling or when making label claims.
REVISED LAB STANDARDS. The use of quality controls in the laboratory now plays an expanded role within the new ISO/IEC 17025:2017 laboratory accreditation standard (revised December 2017), since the known risks are expected to be mitigated through the use of data analysis. While the new version adds additional tools for evaluating risk in product-sample testing, it still requires the laboratory to have procedures and records for monitoring the validity of results such as the regular use of reference materials/internal quality controls and replicate testing. But the list is expanded to include use of additional options, such as alternative instrumentation, functional checks on equipment; use of standards with control charts; intermediate checks; review of reported results; intra-laboratory comparisons; and testing of blind sample(s).
The revised standard uses risk-based thinking throughout and is now in keeping with the same approach as seen in other recent revisions of other related ISO/IEC 17000 series standards (17034 for Reference Material Producers, 17043 for Proficiency Testing providers) and as with the ISO/IEC 9001 management system registration requirements.
RISK AND OPPORTUNITY. One significant new concept that permeates the standard is the adoption of risk- and opportunity-based thinking. Interestingly however, while there are now specific clauses that address risk and opportunity (the first of which deals with risks to impartiality), the new version seems permeated with this approach without always mentioning the word “risk.” The approach has enabled some reduction in what formerly were relatively prescriptive requirements for specific policies and procedures and replaced them with a much more process/outcome-based approach. This leads to the laboratory now having greater flexibility than before in deciding, based on process outcome, the appropriate requirements for specific processes and procedures, details of the documented information, and necessary organizational responsibilities.
This standard now requires the lab to plan and implement actions to address risks and opportunities. As noted in the Introduction of ISO/IEC 17025:2017: ”…addressing both risks and opportunities establishes a basis for increasing the effectiveness of the management system, achieving improved results and preventing negative effects. The laboratory is responsible for deciding which risks and opportunities need to be addressed.” From being mentioned once in the previous standard (4.11.3), risk is now specifically mentioned 30 times throughout the document and found in 12 separate clauses. Yet the changes are significant because, in being less prescriptive and lacking a requirement for a formal approach to risk-based thinking, the tradeoff has been a greater reliance on those quality concepts that focus on controlling anticipated critical control points in the process of managing the testing activities.
Overall, while having different objectives, both QC and QA function in serving the quality needs in mitigating risk. And while QC provides data on how well controlled the manufacturing process is (risk of defect), QA provides data on the process with the subsequent conformity assessment testing (risk of nonconformity to a specification). These both aid the marketplace by helping to provide assurance to regulators and consumers that the manufactured product conforms to the claimed specifications.