OpEx Dictionary

5 Whys is a root cause analysis technique that asks 'why' repeatedly to trace symptoms back to fundamental causes.

5S is a workplace organization methodology using five Japanese principles: Sort, Set in Order, Shine, Standardize, and Sustain.

A3 Problem Solving is a structured approach that documents the problem-solving process on a single 11x17 inch (A3) page.

An affinity diagram organizes large amounts of ideas or data into natural groupings based on relationships, revealing themes and patterns.

Andon is a visual signaling system that alerts teams to problems, status changes, or requests for assistance in real time.

An audit is a systematic, independent examination of processes, systems, or results to verify conformance and identify improvement opportunities.

Autonomous maintenance empowers equipment operators to perform routine maintenance tasks like cleaning, inspection, and lubrication on their own machines.

Availability is the percentage of scheduled time that equipment is actually available for production, accounting for downtime from breakdowns and changeovers.

The Balanced Scorecard is a strategic management framework that measures performance across four perspectives: financial, customer, process, and learning.

Batch size is the quantity of items processed together before moving to the next step - smaller batches enable faster flow.

A benchmark is a standard of excellence or best practice used as a reference point for comparing and improving organizational performance.

A best practice is a method or technique that has consistently shown superior results and is used as a benchmark for others to adopt.

A Black Belt is a full-time Six Sigma practitioner who leads complex improvement projects and mentors Green Belts.

Bottleneck analysis identifies the constraint limiting system throughput, focusing improvement where it matters most.

Breakdown maintenance is reactive repair performed only after equipment fails, addressing problems after they cause production stoppage.

Buffer management monitors the consumption of time or inventory buffers to identify problems early and prioritize improvement efforts.

A Capacity Constrained Resource (CCR) is a resource with capacity close to demand that could become the system constraint with small changes.

Catchball is the back-and-forth dialogue process for aligning goals and plans between organizational levels in hoshin kanri.

Cellular manufacturing organizes equipment and people into cells that produce complete products or components with minimal handling.

A Champion is a senior leader who sponsors Six Sigma projects, removes organizational barriers, and ensures resources and support for project success.

Change management is a structured approach to transitioning individuals, teams, and organizations from current state to desired future state.

Changeover is the process of converting equipment from producing one product to another, including setup, adjustment, and trial runs.

The Coaching Kata is a structured pattern of questions that develops scientific thinking in others through guided practice.

Common cause variation is the natural, inherent fluctuation in a process that occurs randomly and requires system-level changes to reduce.

Condition monitoring tracks equipment health indicators in real-time to detect degradation and predict failures before they occur.

A constraint is the single factor that most limits a system's ability to achieve its goal, determining overall throughput.

Constraint management focuses improvement on the system bottleneck to maximize throughput with minimal investment.

Continuous improvement is the ongoing effort to enhance products, services, or processes through incremental and breakthrough improvements.

A control chart is a statistical tool that monitors process variation over time, distinguishing between common cause and special cause variation.

A control plan documents the system for maintaining process improvements, specifying what to monitor, how to measure, and how to respond to deviations.

Corrective action is a systematic process for eliminating the root cause of an identified problem to prevent recurrence.

Cost of Quality (COQ) measures the total cost of ensuring quality and the cost of failing to achieve it—prevention, appraisal, and failure costs.

Cpk is a process capability index that measures how well a process performs relative to specification limits, accounting for both variation and centering.

Cross-training develops employees in multiple skills or job functions to increase workforce flexibility and eliminate single points of failure.

CTQ (Critical to Quality) characteristics are the measurable product or process attributes that directly impact customer satisfaction.

The Current Reality Tree is a TOC logic diagram that maps cause-and-effect relationships to identify core problems underlying multiple symptoms.

Customer focus is the practice of understanding and prioritizing customer needs as the basis for all operational decisions.

Cycle time is the elapsed time to complete one unit of work from start to finish of a specific process step.

Daily management is a system of standardized routines for monitoring performance, identifying problems, and initiating rapid response at the work level.

A dashboard is a visual display of key metrics and information designed to provide at-a-glance understanding of performance status.

DFSS (Design for Six Sigma) is a methodology for designing new products or processes to achieve Six Sigma quality levels from the start.

DMADV is the five-phase Design for Six Sigma methodology: Define, Measure, Analyze, Design, and Verify for creating new products or processes.

DMAIC is the five-phase problem-solving methodology used in Six Sigma: Define, Measure, Analyze, Improve, and Control.

DOE (Design of Experiments) is a statistical method for systematically testing multiple factors simultaneously to determine their effects on outcomes.

DPMO (Defects Per Million Opportunities) is a Six Sigma metric that measures process quality by calculating defects relative to total opportunities.

Drum-Buffer-Rope is a TOC scheduling method that synchronizes production to the constraint, protects it with buffers, and controls material release.

Early equipment management applies TPM lessons learned to new equipment design and installation, building maintainability in from the start.

Elevate is the fourth of TOC's Five Focusing Steps—investing to increase constraint capacity after exploitation is maximized.

The Evaporating Cloud is a TOC conflict resolution tool that surfaces hidden assumptions to find solutions where both sides win.

Exploit is the second of TOC's Five Focusing Steps—maximizing output from the constraint using existing resources before investing in capacity.

FIFO (First In, First Out) ensures items are processed or consumed in the order they arrived, preventing aging and maintaining flow.

First Pass Yield (FPY) is the percentage of units that complete a process step correctly the first time without rework, repair, or rejection.

A fishbone diagram organizes potential causes of a problem into categories, visually structured like fish bones around a spine.

The Five Focusing Steps are TOC's continuous improvement cycle: Identify the constraint, Exploit it, Subordinate to it, Elevate it, and Repeat.

Flow is the continuous movement of products, services, or information through value-creating steps without interruption, batching, or backflow.

FMEA (Failure Mode and Effects Analysis) is a systematic method for identifying potential failures, their causes, and effects to prioritize preventive actions.

Focused improvement (Kobetsu Kaizen) is the TPM pillar that uses cross-functional teams to eliminate specific equipment and process losses systematically.

The Future Reality Tree is a TOC logic tool that tests whether proposed solutions will achieve desired outcomes and identifies potential negative effects.

Gage R&R (Repeatability and Reproducibility) is a study that quantifies measurement system variation to ensure data quality for process improvement.

Gap analysis is a method for comparing current state to desired future state to identify the gaps that must be addressed to achieve goals.

Gemba means 'the real place' - the location where work happens and value is created, where leaders must go to understand actual conditions.

A gemba walk is a structured observation of the workplace where leaders go to see, ask questions, and understand actual conditions.

Genba kanri is workplace management - the system of daily management practices that maintain and improve performance.

Genchi Genbutsu means 'go and see for yourself' - the practice of direct observation at the source to understand the actual situation.

Go and See is the practice of personally observing work at the actual location rather than relying on reports or secondhand information.

A Green Belt is a part-time Six Sigma practitioner who leads smaller improvement projects while maintaining regular job responsibilities.

Hansei is the practice of critical self-reflection to acknowledge mistakes, understand root causes, and commit to improvement.

Heijunka is production leveling - smoothing the volume and mix of production to reduce variability and enable consistent flow.

A heijunka box is a visual scheduling tool that levels production by distributing work evenly across time periods.

The hidden factory is the informal collection of rework, repair, and correction activities that consume resources but don't appear in official metrics.

A histogram is a bar chart showing the frequency distribution of continuous data, revealing patterns in process variation and shape.

Hoshin Kanri is a strategic planning methodology that aligns organizational goals with daily actions through collaborative goal deployment.

An hourly production board tracks output versus target each hour, making performance and problems visible in real time.

The Improvement Kata is a four-step practice routine for developing scientific thinking and systematic problem-solving skills.

An Ishikawa diagram is a cause-and-effect diagram developed by Kaoru Ishikawa for systematic root cause analysis.

Jidoka is automation with a human touch - building quality into the process by stopping immediately when a defect is detected.

Job Instruction is a structured method for training workers quickly and correctly using job breakdown sheets and a four-step teaching process.

Just-in-Time (JIT) is a production strategy that produces only what is needed, when it is needed, in the amount needed.

Kaizen is the philosophy of continuous, incremental improvement involving everyone in an organization to eliminate waste and improve processes.

A kaizen blitz is an intensive, rapid improvement event focused on making immediate changes to a specific process.

A kaizen event is a focused, time-boxed improvement activity where a team intensively improves a specific process.

Kamishibai boards are visual audit systems using cards to ensure regular checks of process conditions and standards.

Kanban is a visual signal system that triggers production or movement of materials based on actual consumption.

The Kano Model categorizes customer requirements into must-haves, performance factors, and delighters to guide product and service design priorities.

Kata is a structured routine or pattern that, through practice, builds capability and becomes second nature.

A KPI (Key Performance Indicator) is a measurable value that demonstrates how effectively an organization achieves key business objectives.

A lagging indicator is a results metric that reports performance after the fact, confirming what has already occurred.

Lead time is the total elapsed time from when a request is made until it is fulfilled - the customer's experience of waiting.

Leader standard work is a defined routine of activities that ensures leaders regularly perform essential management tasks like gemba walks and coaching.

A leading indicator is a predictive metric that signals future performance, enabling proactive intervention before results materialize.

Lean leadership is a management approach where leaders develop people, enable improvement, and create conditions for sustainable performance excellence.

Lean thinking is a management philosophy focused on maximizing customer value while minimizing waste through the five lean principles.

Leveling is the practice of smoothing workload over time to eliminate peaks and valleys that cause waste and overburden.

Line balancing distributes work elements across workstations to achieve even cycle times close to takt time.

A Master Black Belt is an expert Six Sigma practitioner who trains and mentors Black Belts, develops methodology, and guides organizational deployment.

A maturity model is a framework that describes progressive levels of capability development, from initial to optimized states.

Measurement System Analysis (MSA) is a collection of methods for evaluating whether a measurement system provides reliable, accurate data for decision-making.

A milk run is a fixed-route delivery system that picks up and delivers materials on a regular schedule, like traditional milk delivery.

Minor stops are brief equipment interruptions lasting under 5 minutes that individually seem insignificant but collectively cause major productivity loss.

Mistake-proofing is designing processes and devices to prevent human errors or make them immediately detectable.

Monozukuri is the Japanese philosophy of making things with craftsmanship, pride, and continuous pursuit of excellence.

MTBF (Mean Time Between Failures) measures average equipment reliability by calculating the average operating time between breakdowns.

MTTR (Mean Time To Repair) measures average maintenance responsiveness by calculating the average time to restore failed equipment to operation.

Muda refers to waste in any process - activities that consume resources without creating value for the customer.

Mura refers to unevenness or inconsistency in processes that causes waste and makes work unpredictable.

Muri refers to overburden or unreasonable stress placed on people or equipment beyond their capacity.

Nemawashi is the Japanese practice of building consensus through informal discussions before formal decisions are made.

Obeya is a 'big room' where cross-functional teams co-locate to manage projects with visual displays of status and plans.

OEE (Overall Equipment Effectiveness) measures manufacturing productivity by combining availability, performance, and quality into a single percentage.

One-piece flow is the ideal state where items move through processes one at a time without batching, waiting, or accumulation.

Operational excellence is a philosophy of continuous improvement that engages everyone in systematic, sustainable enhancement of business performance.

A Pareto chart combines bar and line graphs to show which factors contribute most to a problem, guiding improvement priorities.

PDCA (Plan-Do-Check-Act) is a four-step continuous improvement cycle for testing changes and learning from results.

PDSA (Plan-Do-Study-Act) is Deming's refined improvement cycle emphasizing studying results to understand why, not just what happened.

Planned maintenance is scheduled, proactive equipment maintenance performed at predetermined intervals to prevent breakdowns and extend equipment life.

Poka-yoke is mistake-proofing - designing processes and devices to prevent errors or make them immediately obvious.

Policy deployment is a strategic planning process that aligns organizational goals from top to bottom through cascading objectives and catchball dialogue.

Predictive maintenance uses condition monitoring and data analysis to predict equipment failures and schedule maintenance before breakdowns occur.

Preventive action is a proactive process for eliminating potential causes of problems before they occur, based on risk analysis.

Preventive maintenance is scheduled, time-based or usage-based maintenance performed at regular intervals to prevent equipment failures.

Process capability measures how well a process meets specification requirements, comparing natural process variation to allowable tolerance.

A project charter is a document that formally authorizes an improvement project, defining its scope, goals, team, and expected benefits.

Psychological safety is a shared belief that the team is safe for interpersonal risk-taking—speaking up, asking questions, and admitting mistakes.

A pull system produces only when downstream processes signal demand, preventing overproduction and enabling flow.

A push system produces based on forecasts and schedules, pushing work downstream regardless of actual demand.

A quality circle is a small group of employees who meet regularly to identify, analyze, and solve work-related quality and productivity problems.

Quality maintenance is the TPM pillar focused on maintaining equipment conditions that produce zero-defect output through equipment precision and stability.

Quick changeover is the practice of reducing the time required to switch equipment or processes from one product to another.

Reliability Centered Maintenance (RCM) is a systematic process for determining the most effective maintenance approach for each equipment failure mode.

Respect for People is a foundational lean principle that values human potential, dignity, and development alongside process improvement.

Ringi is the Japanese consensus-based decision-making process where proposals circulate for approval through multiple levels.

Rolled Throughput Yield (RTY) measures the probability that a unit passes through an entire process without any defects or rework at any step.

Root cause analysis is a systematic process for identifying the fundamental reasons why problems occur, enabling permanent corrective action.

A run chart plots data points in time sequence to reveal trends, shifts, cycles, or patterns that indicate process changes.

A scatter diagram plots two variables against each other to reveal relationships, correlations, or patterns between potential causes and effects.

Seiketsu is the fourth of the 5S steps - creating standards and systems to maintain Sort, Set in Order, and Shine.

Seiri is the first of the 5S steps - sorting through items to remove what is unnecessary from the workplace.

Seiso is the third of the 5S steps - cleaning the workplace thoroughly while inspecting for abnormalities.

Seiton is the second of the 5S steps - organizing remaining items so everything has a designated, labeled place.

Servant leadership is a philosophy where leaders prioritize serving their teams—enabling success by removing obstacles and providing support.

Setup reduction focuses on minimizing the time and effort required to change from one product, batch, or configuration to another.

A shadow board organizes tools with painted outlines showing each tool's designated location, making missing items immediately obvious.

Shitsuke is the fifth of the 5S steps - maintaining discipline through training, audits, and continuous practice.

Sigma level is a statistical measure of process capability that indicates how many standard deviations fit between the process mean and specification limits.

SIPOC is a high-level process map showing Suppliers, Inputs, Process, Outputs, and Customers to define project scope and stakeholders.

The six big losses are the primary categories of equipment productivity loss that TPM targets: breakdowns, setup, idling, speed loss, defects, and startup.

Six Sigma is a data-driven methodology for eliminating defects and reducing variation in processes to achieve near-perfect quality.

A skill matrix is a visual tool showing team members' competency levels across required skills to identify gaps and guide development.

SMED (Single-Minute Exchange of Die) is a systematic approach to reducing changeover time to under ten minutes.

A spaghetti diagram traces the path of movement through a workspace, revealing inefficient layouts and excessive travel.

Special cause variation is unusual process fluctuation from specific, identifiable sources that can be investigated and eliminated.

Speed loss is the gap between actual equipment running speed and its designed maximum rate, reducing output without causing stops.

Stability is the foundational state of predictable, reliable processes that enables continuous improvement and lean operations.

Standard work documents the best-known sequence, timing, and layout for performing work consistently and safely.

Standardization is establishing and following the current best-known method for performing work consistently and predictably.

Statistical Process Control (SPC) uses statistical methods to monitor and control processes, distinguishing normal variation from signals requiring action.

Subordinate is the third of TOC's Five Focusing Steps—aligning all non-constraint resources to support and never impede constraint performance.

A suggestion system is a structured process for collecting, evaluating, and implementing employee improvement ideas with recognition and feedback.

A supermarket is a controlled inventory location where products are stored for downstream pull, similar to retail supermarket shelves.

A takt board displays takt time and actual cycle time, showing whether production is keeping pace with customer demand.

Takt time is the pace of production needed to match customer demand - the heartbeat that synchronizes all work.

Theory of Constraints (TOC) is a management philosophy that focuses improvement efforts on the system constraint that limits overall performance.

Thinking Processes are TOC logic tools for analyzing complex situations, identifying root causes, and developing effective solutions.

Throughput is the rate at which a system produces finished goods or services - the output over a given time period.

Throughput Accounting is a TOC decision-making method that evaluates choices based on their impact on Throughput, Inventory, and Operating Expense.

Tiered accountability is a management system with cascading meetings that escalate unresolved issues from frontline to leadership on a defined schedule.

Time study is the systematic measurement and analysis of work element times to establish standards and identify improvement opportunities.

A tollgate is a formal review checkpoint between DMAIC phases where leadership validates that required deliverables are complete before proceeding.

Total Productive Maintenance (TPM) is a holistic approach to equipment maintenance that maximizes equipment effectiveness through operator involvement and proactive care.

The Toyota Production System (TPS) is Toyota's integrated manufacturing approach combining just-in-time, jidoka, and respect for people.

The Toyota Way is Toyota's management philosophy built on two pillars: continuous improvement and respect for people.

Training Within Industry (TWI) is a structured methodology for developing supervisory skills in job instruction, job methods, and job relations.

True North is the ideal state or perfect vision that guides continuous improvement direction, even if never fully achieved.

A U-shaped cell arranges equipment in a U configuration, minimizing walking distance and enabling flexible staffing.

Value is any action or process that the customer is willing to pay for - the starting point for lean thinking.

A value stream is the complete sequence of activities required to transform raw materials or information into a product or service delivered to the customer.

Value Stream Mapping (VSM) is a visual tool for analyzing material and information flow from customer order to delivery.

Variance analysis is the process of comparing actual results to planned or expected values to understand the reasons for differences.

Vibration analysis is a condition monitoring technique that detects equipment problems by analyzing mechanical vibration patterns and frequencies.

Visual controls are mechanisms that make standards and abnormalities immediately visible without requiring inspection or data analysis.

Visual management uses visual signals and displays to make process status, performance, and abnormalities immediately obvious.

Voice of Customer (VOC) is the structured process of capturing customer needs, expectations, and preferences to guide product and process design.

Waste is any activity that consumes resources without creating value for the customer - the target of lean improvement.

A water spider is a material handler who replenishes production areas, enabling operators to focus on value-adding work.

Work in Process (WIP) is all the material, information, or work that has started but not yet completed - inventory between process steps.

Work instructions are detailed step-by-step directions for performing specific tasks correctly and consistently.

Work sampling estimates time proportions spent on activities through random observations rather than continuous measurement.

Yamazumi is a visual stacked bar chart showing work element times against takt time to reveal imbalances and improvement opportunities.

A Yellow Belt has foundational Six Sigma knowledge to participate on project teams and apply basic improvement concepts in daily work.

Yokoten is the horizontal deployment of learnings and best practices across an organization to multiply improvement impact.