Maintenance & CMMS Glossary

Core Terms

CMMS: Computerized Maintenance Management System used to plan, execute and analyze maintenance.
EAM: Enterprise Asset Management – broader processes and tools around asset lifecycle beyond maintenance.
Asset: Equipment, line, building or component managed throughout its lifecycle.
Work Order (WO): Task with scope, priority, assignee, due date and completion record.
Work Request: Structured input for a maintenance need that can be approved and converted to a work order.
Wrench Time: Percentage of a technician’s shift spent on actual hands-on work (excludes travel, waiting, admin).

MTTR: Mean Time To Repair – average time to restore a failed asset.
MTBF: Mean Time Between Failures – average time between two failures.
MTTF: Mean Time To Failure – average time to the first failure (non-repairable items).
Availability: Uptime as a percentage of total time (can be planned or unplanned).
OEE: Overall Equipment Effectiveness = Availability × Performance × Quality.
Backlog: Sum of outstanding maintenance work (often measured in labor hours or weeks).

Preventive Maintenance (PM): Planned maintenance based on time, meter or condition.
Corrective Maintenance: Work performed to restore functionality after a failure.
Predictive Maintenance (PdM): Data-driven maintenance using condition monitoring (vibration, thermography, oil, etc.).
RCM: Reliability-Centered Maintenance – method for defining the optimal maintenance strategy by function and failure mode.
FMEA: Failure Mode and Effects Analysis – systematic analysis of failure modes and their impact.
RCA: Root Cause Analysis – method to identify underlying causes of problems and prevent recurrence.

Spare Parts: Items kept in stock for maintenance interventions.
BOM: Bill of Materials – list of parts for an asset.
Reorder Point (ROP): Stock level at which a replenishment is triggered.
Cycle Count: Ongoing inventory verification by counting subsets of stock on a schedule.
Issue/Receipt: Movement of parts out of/into stores for maintenance jobs.

SOP: Standard Operating Procedure – documented process for consistent execution.
LOTO: Lockout/Tagout – safety procedure to ensure equipment is properly shut off.
Calibration: Adjustment and verification of measuring instruments.
HACCP: Hazard Analysis and Critical Control Points – food safety management.
GxP: Good practice quality guidelines and regulations (e.g., GMP, GLP) in life sciences.

SSO: Single Sign-On – centralized authentication across systems.
Active Directory / Entra ID: Enterprise identity provider for users and groups.
API & Webhooks: Interfaces to integrate ERP, inventory, BI and more.
Barcode/QR: Codes used for rapid identification of assets and parts.
Excel Import: Bulk import tool for assets, parts, stores and suppliers (e.g., MMCImportFromExcel).

CMMS: Computerized Maintenance Management System used to plan, execute and analyze maintenance.
EAM: Enterprise Asset Management – broader processes and tools around asset lifecycle beyond maintenance.
Asset: Equipment, line, building or component managed throughout its lifecycle.
Work Order (WO): Task with scope, priority, assignee, due date and completion record.
Work Request: Structured input for a maintenance need that can be approved and converted to a work order.
Wrench Time: Percentage of a technician’s shift spent on actual hands-on work (excludes travel, waiting, admin).

MTTR: Mean Time To Repair – average time to restore a failed asset.
MTBF: Mean Time Between Failures – average time between two failures.
MTTF: Mean Time To Failure – average time to the first failure (non-repairable items).
Availability: Uptime as a percentage of total time (can be planned or unplanned).
OEE: Overall Equipment Effectiveness = Availability × Performance × Quality.
Backlog: Sum of outstanding maintenance work (often measured in labor hours or weeks).

Preventive Maintenance (PM): Planned maintenance based on time, meter or condition.
Corrective Maintenance: Work performed to restore functionality after a failure.
Predictive Maintenance (PdM): Data-driven maintenance using condition monitoring (vibration, thermography, oil, etc.).
RCM: Reliability-Centered Maintenance – method for defining the optimal maintenance strategy by function and failure mode.
FMEA: Failure Mode and Effects Analysis – systematic analysis of failure modes and their impact.
RCA: Root Cause Analysis – method to identify underlying causes of problems and prevent recurrence.

Spare Parts: Items kept in stock for maintenance interventions.
BOM: Bill of Materials – list of parts for an asset.
Reorder Point (ROP): Stock level at which a replenishment is triggered.
Cycle Count: Ongoing inventory verification by counting subsets of stock on a schedule.
Issue/Receipt: Movement of parts out of/into stores for maintenance jobs.

SOP: Standard Operating Procedure – documented process for consistent execution.
LOTO: Lockout/Tagout – safety procedure to ensure equipment is properly shut off.
Calibration: Adjustment and verification of measuring instruments.
HACCP: Hazard Analysis and Critical Control Points – food safety management.
GxP: Good practice quality guidelines and regulations (e.g., GMP, GLP) in life sciences.

SSO: Single Sign-On – centralized authentication across systems.
Active Directory / Entra ID: Enterprise identity provider for users and groups.
API & Webhooks: Interfaces to integrate ERP, inventory, BI and more.
Barcode/QR: Codes used for rapid identification of assets and parts.
Excel Import: Bulk import tool for assets, parts, stores and suppliers (e.g., MMCImportFromExcel).