Quality Assurance and Management: Concepts and Principles
Quality Assurance and Management
Q. Definition:
- Comparative Sense (Degree of Excellence): On a relative basis, products can be ranked or referred to by “grade”.
- Quantitative Sense (Used in Manufacturing/Production Release/Technical Evaluation): Refers to quality level.
- Fitness for Purpose Sense: Evaluation of a product’s or service’s ability to satisfy a given need.
Gap Between Perception & Expectation
Expected Service = Word of Mouth + Personal Needs + Past Experience (manufacturer -> specification -> [delivery -> perceived] & external communication -> expected & perceived)
- Manufacturer/Expected: Customers do not always know all necessary features.
- Manufacturer/Specification: Resource/technical limitations.
- Specification/Delivery: Production defects.
- Delivery/External Communication: Overpromising and under-delivering. Promise realistically and over-deliver.
- Expected/Perceived: Actual and realized unwillingness and inability.
Q. Dimensions:
Performance, Features, Reliability, Conformance, Durability, Serviceability, Aesthetics, Perceived Quality
- Performance: A product’s primary operating characteristic (e.g., car: noise level, TV: sound and picture quality). Measurable and can be used to objectively/subjectively rank different brands based on individual aspects of performance.
- Features: Secondary aspects supplementing basic functions. Objectively measurable and reflect individual needs.
- Reliability: Probability of product malfunction/failure within a period of time. Measured by Mean Time To Failure (MTTF), Mean Time Between Failures (MTBF), and failure rate. Impacts the cost of maintenance and downtime.
- Conformance: Degree to which a product’s design and operating characteristics meet specifications. Specifications define a center and a range of allowable deviation. Neglecting dispersion within the specification limits can lead to losses (loss function curve).
- Durability: Amount of use before breakdown. Measured by Mean Time To Unrepair (MTTunrepair). Linked with reliability. Neglects external factors (e.g., increased oil prices & economic downturn => fewer miles driven => increased product life).
- Serviceability: Speed, courtesy, competence, ease of repair, and other service aspects.
- Aesthetics: Reflects a product’s look, feel, taste, and smell.
- Perceived Quality: Formed by customer-made inferences about product quality, which may be greater than reality.
Q. Cycle
Customer: Specifies quality needs (Needs) -> Marketing: Interprets customer needs; works with customers to design products to fit operations (Interpretation of needs) -> Engineering: Defines design concepts; prepares specifications; defines quality characteristics (Specifications) -> Operations: Produces products/services; Quality Control: Plans and monitors quality (Production) -> LOOP
What is a QA System?
Quality Problems -> Organization-wide QA System -> [Marketing & Sales, Engineering Design, Process Engineering, Manufacturing Engineering, Manufacturing, Purchasing, Quality, Packing & Shipping, Field Service] -> Quality Delivery Process
Evolution & Scope of the QA Concept
A. Inspection-oriented assurance -> B. Process control-oriented assurance -> C. Assurance with emphasis on systems & new product development
A. Inspection was strengthened to achieve quality assurance. Japan banned it, while the West and Hong Kong equated QA with inspection. This was based on the assumption that supervisors must be strict with workers, leading to increased authority and independence of the inspection division, and a higher percentage of inspectors to line workers (Japan: 1-5%, West: 15%).
Problems:
- Inspection requires unnecessary personnel, reducing productivity and increasing costs.
- Inspection alone cannot assure quality, especially for complex assembled products relying on reliability tests.
- Responsibility for QA rests solely on inspectors.
- Information feedback from the inspection division to manufacturing is too slow.
- Conceptual barriers hinder seeking higher quality through statistical sampling with Acceptable Quality Level (AQL).
B. “Quality must be built into each process” emphasizes process control. It involves studying process capability and ensuring products meet quality standards through manufacturing process control. This approach expands to cover suppliers and subcontractors.
Problems:
- Doesn’t address product use by consumers: different conditions of use, misuse, miscommunication, misinterpretation of quality information and customer requirements.
- Production/inspection alone cannot solve problems that occur in design, development, management, and communication processes.
- Therefore, process control must continue, but QA should begin at the planning and development stages from a systems perspective.
C. Emphasizes an overall quality management system (steps: marketing, planning new products, design, prototype making, testing, subcontracting, purchasing, process design, trial production, regular production, marketing, distribution, after-sales service). Procedures, documentation, and evaluation must be tightly conducted and assured. Adequate performance quality analysis (identifying customer requirements, evaluating quality) should be done before manufacturing to build QA into the entire product and process.
Components of a QA System
A defined QA system outlines all activities and responsibilities associated with quality through policies and procedures. The system should be documented so that personnel in different functions understand their own responsibilities and those of others. This documentation serves as a baseline for auditing and making improvements in the system, and as a basis for training personnel in quality functions. A QA system should have specific objectives. A planned, correctly implemented QA system with covered procedures is necessary to achieve these objectives. Different components/subsystems are designed and implemented to form integral parts of a typical QA system. Typical major QA system components/subsystems include: quality policy & objectives, inspection system, calibration system, non-conformance system, corrective action system, quality performance reporting system, and prevention system.
ISO 9000:2005 8 Quality Management Principles
Customer-focused organization, leadership, involvement of people, process approach, systems approach to management, continual improvement, factual approach to decision making, mutually beneficial supplier relationships
ISO 9001:2008 8 Sections
Scope, normative references, terms & definitions, quality management system, management responsibility, resource management, product realization, measurement, analysis & improvement
ISO 9000 Documentation System
Tiered Structure:
- Quality Manual
- Departmental Manuals & Procedures
- Work Instructions
- Forms & Records
Third-Party Registration & Certification
Third-party schemes were part of the original development of ISO 9000. Certification serves as a benchmark for an organization’s QA system. ISO 9000 is a globally recognized quality system standard due to its widespread acceptance. It serves as a basic qualification for selecting quality suppliers in international business.
Changing Customer-Supplier Relationships: There is a growing trend towards fewer, larger manufacturers and closer relationships with suppliers (including virtual incorporation of parts of administrative and control systems). This is evident in two areas: the use of Electronic Data Interchange and the adoption of compatible Quality Management Systems (QMS). Suppliers respond to customer QMS demands by both operating under a common international standard, ISO 9000. The standard is being forced globally downward from large manufacturers to suppliers and sub-suppliers.
Third-Party Audit Concept: In a two-party system, the supplier develops a QA system conforming to the ISO 9000 standard, and the customer audits the system for acceptance. Two-party systems involve suppliers and customers participating in multiple audits, which is costly. This can be replaced by a third-party registration system.
ISO 9000 quality system registration involves assessment and periodic audits of adequacy by a third-party registrar. If the system conforms to the registrar’s interpretation of the ISO 9000 standard, a certificate of registration is issued to the supplier. This registration assures potential customers that the supplier has a well-monitored quality system, eliminating the need for multiple audits.
ISO 9000 Quality Strategy
The ISO 9000 quality strategy can be visualized as a “Quality Wheel” (Plan-Do-Check-Act cycle) ascending the ISO 9000 staircase, with a Continuous Quality Improvement (CQI) arrow indicating the uplifting of quality levels and requirements.
Contemporary Quality Concepts
Taylor – Inspection Quality; Shewhart – Process Control Quality; Deming – Quality Management; Juran – Cost of Quality; Feigenbaum – Total Quality Control; Crosby – Quality is Free; Ishikawa – Preventive Quality; Taguchi – Design Quality; Garvin – Service Quality; Dale – Cultural Change
Deming’s 14 Points
Deming’s 14 points are essential for businesses to survive and remain competitive. They can shape new attitudes towards work and create a work environment that fosters continuous improvement.
- Constancy of Purpose: Focus on quality improvement to remain competitive.
- New Philosophy: Embrace modern management principles. Awaken to the need for change, learn responsibility, take leadership for change, and do not accept delays, mistakes, defective materials, or poor workmanship.
- Cease Dependence on Mass Inspection: Build quality into the product/process from the start.
- End the Practice of Awarding Business on Price Tag Alone: Minimize total cost by working with a single supplier for each item, fostering long-term relationships of loyalty and trust.
- Improve Constantly and Forever: Continuously improve the system of production and service to increase quality and productivity while reducing costs.
- Institute Training on the Job: Implement modern training methods.
- Institute Leadership: Overhaul supervision to help people and machines do a better job.
- Drive Out Fear: Create an environment where everyone can work effectively for the company.
- Break Down Barriers Between Departments: Work as a team to foresee and solve problems.
- Eliminate Slogans, Exhortations, and Targets: Avoid asking for zero defects without providing the necessary methods and resources.
- Eliminate Work Standards and Numerical Quotas: Do not manage by objectives (MBO) or by numbers and numerical goals. Substitute both with leadership.
- Remove Barriers to Pride of Workmanship: Restore pride in work.
- Institute a Vigorous Program of Education and Self-Improvement: Encourage continuous learning.
- Put Everybody in the Company to Work to Accomplish the Transformation: Company-wide commitment and action are needed to implement these 13 points.
Deadly Diseases
Major obstacles to implementing Deming’s philosophy include: lack of constancy of purpose, preoccupation with short-term profits, reliance on visible figures, performance appraisals, and managerial job mobility.
Juran Trilogy
The Juran Trilogy focuses on Quality Planning (QP), Quality Control (QC), and Quality Improvement (QI). The cost of poor quality as a percentage of the operating budget changes over time.
Initially, QC during operations accounts for around 20% of the budget (original zone of QC and chronic waste, representing opportunities for improvement). This can spike to 40% due to sporadic issues. Through QI, this percentage is reduced to 5%, establishing a new zone of QC.
Usual Company Effectiveness in Implementing the Trilogy
Based on self-assessment by managers and prevailing processes, companies often prioritize QC, resulting in strong QC practices but weak QP and QI.
Common Teachings of Quality Gurus
Although their approaches differ in techniques, emphasis, and application, quality gurus share a common goal: continuous improvement. Their objective is to continuously improve every output by removing unwanted variation and improving underlying work processes.