Non-conformity is one of the key concepts within any quality management system in industrial environments.
When a it is not identified or properly managed, it can become a direct source of inefficiencies, extra costs, and loss of productivity, as well as hinder the continuous improvement of the organization.
Understanding what a non-conformity is, how it is classified, and the proper treatment allows industrial companies to reduce risks, optimize processes, and improve customer satisfaction.
In this article, we examine in detail their impact and best practices for managing them.
What is a quality non-conformity
A quality non-conformity is an unexpected event that occurs during the manufacturing or service delivery process and indicates that a previously defined requirement has not been met.
According to ISO 9000:2015, a non-conformity is directly related to the failure to meet a requirement of the quality management system, whether internal or external.
A non-conformity can appear at any stage of the production cycle—from design to final delivery—and may originate from human errors, material failures, process deficiencies, or issues with equipment and infrastructure.
Early detection of a non-conformity is essential to limit its impact and avoid consequences such as customer complaints, product safety risks, or damage to the company’s reputation.
Types of non-conformity in a quality management system
Non-conformities can be classified from different perspectives, which facilitates their analysis and management.
Internal
An internal non-conformity occurs when procedures, instructions, or requirements defined by the organization itself are not followed.
Example: an operator does not properly follow the established temperature control procedure, causing the product not to meet internal quality criteria.
External
An external non-conformity is associated with the failure to comply with regulatory requirements, certifications (ISO, IFS, BRC, etc.), or specifications agreed upon with clients or suppliers.
Example: raw materials supplied by a vendor that do not meet the agreed technical specifications.
Major
A major non-conformity compromises the effectiveness of the quality management system or poses a serious risk to the client or product.
Example: the production of a cosmetic with incorrect dosing due to a quality control failure.
Minor
A minor non-conformity corresponds to occasional deviations that do not significantly affect product quality or system integrity.
Example: incomplete quality records or documentation errors with no impact on the final product.
Real
A real non-conformity has objective evidence of non-compliance, allowing immediate corrective actions to be taken.
Example: out-of-tolerance products detected through inline measurements.
Potential
A potential non-conformity has not yet materialized, but there are indications that allow anticipating a possible future non-compliance.
Example: uncommunicated changes in a supplier’s production process.
Non-conformity in ISO 9001
Managing non-conformities is a central element in systems based on the ISO 9001:2015 standard, one of the most widely implemented quality standards in industry.
In an ISO 9001 system, non-conformities are usually related to:
- Unmet technical product requirements.
- Deviations in production processes.
- Human errors due to lack of training.
- Improper use of equipment.
- Failures to meet deadlines or quantities.
Proper treatment of non-conformities is key to maintaining certification and ensuring continuous system improvement.
Impact of non-conformity in an industrial company
Poorly managed non-conformities can have serious consequences for an organization:
- Increased costs of poor quality.
- Loss of efficiency and productivity.
- Delays in production and delivery.
- Complaints and returns.
- Deterioration of brand image.
However, when managed correctly, it becomes an opportunity for improvement, allowing processes to be reinforced and future errors prevented.
Corrective and preventive actions
Treating a non-conformity relies on two types of actions:
Corrective action: applied when it has already occurred, aiming to eliminate the root cause and prevent recurrence.
Preventive action: implemented before it occurs, reducing potential risks.
Both are essential in an effective quality management system.
Step-by-step treatment
Structured treatment of a non-conformity usually follows five steps:
- Detection and recording of the non-conformity.
- Immediate correction of the non-compliance.
- Root cause analysis (e.g., using the 5 Whys technique).
- Definition and implementation of corrective actions.
- Verification of action effectiveness.
Only when it is confirmed that the problem does not reoccur can the process be considered closed.
Example of non-conformity and corrective action in industry
In a company producing plastic containers for the food industry, a non-conformity is detected when several batches show deformations during a quality inspection.
Analysis reveals a variation in the molding process temperature. The corrective action includes parameter adjustments, staff training, and real-time quality controls. A preventive maintenance plan is also implemented to avoid recurrence of the non-conformity.
Managing non-conformity with MES systems
In industrial environments, MES systems are a key tool for managing quality non-conformities.
These systems allow real-time deviation detection, non-conformity recording, and monitoring of corrective and preventive actions.
MES quality modules enable:
- Immediate visibility of non-conformities.
- Root cause analysis based on real data.
- Full traceability of the process.
- Reduction of costs associated with poor quality.
Solutions like Mapex MES help industrial companies systematically manage non-conformities, reinforcing continuous improvement and data-driven decision-making.
FAQs about non-conformity
What is the difference between non-conformity and defect?
A non-conformity refers to the failure to meet a quality system requirement, whereas a defect is a non-conformity that directly affects the product as perceived by the customer.
What types of non-conformity exist?
The most common types in a quality management system are: internal and external non-conformities (based on origin); major and minor (based on severity); and real and potential (based on the existence of objective evidence).
Should all non-conformities be recorded?
Yes. Recording them is essential for analysis, traceability, and continuous improvement, especially in ISO 9001 systems.
Who can detect them?
Any stakeholder: internal staff, clients, suppliers, external auditors, or regulatory authorities.
What happens if it is not corrected?
It can lead to additional costs, customer loss, sanctions, and reputational damage, in addition to compromising operational efficiency.
What role does an MES play in non-conformity management?
An MES system automates detection, recording, and tracking of non-conformities, improving response time and effectiveness of corrective actions.
