Definitions and terms found in the maintenance industry

ADA Building Regulations

U.S. standards institutions, both private and public, that aims to eliminate discrimination against disabled people.

Agricultural Maintenance

To make sure farming machinery is up-and-running when needed. Food producers must ensure food are kept clean and safe for consumption.

AHR Expo

A unique opportunity where manufacturers of all specialties and sizes come together to showcase the future of HVACR technologyand share ideas.


Widely used by municipalities, airports, oil and gas industries as well as multinational corporations. It is designed for collecting, managing, evaluating, and storing geographical asset data.


An American professional association aiming to advance ventilation, heating, refrigeration systems design and construction and air conditioning.

Asset Hierarchy

Index of all equipment, tools and machines and how it functions together.

Asset Lifecycle

The stage through which an asset goes, from planning to exposal.

Asset Management

The control and planning that accompanies the acquisition of an asset and the system of actions that businesses perform to get value from it.

Asset Management PAS 55

PAS 55 provides guidance on all aspects of sound asset lifecycle management, from initial need and acquisition to maintenance decisions (cost/risk/performance) to renewal, modification, and disposal.

Asset Perfromance Management

A set of tools that aim to limit risk and cost and improve equipment reliability and availability.

Asset Register

A compilation of assets in an organization, together with information about the make, model, vendor and manufacturer.

Asset Tracking

The way in which organizations keep track of their equipment and inventory.

Augmented Reality

The process of involving smart technology in the training of important maintenance procedures to maintenance professionals.

Autonomous Maintenance

Empowering machine operators to decide on maintenance procedures without the help of a maintenance professional.


The amount of total time a piece of machinery is able to perform its specific actions.


Work that has not been completed by the required date. The time that a work order is seen as being overdue.

Backup Generator

A machine that provides electricity during an electricity outage. Could be either whole-house or portable.

BACnet alarms

A communication protocol for Building Automation and Control (BAC) networks that leverage the ASHRAE, ANSI, and ISO 16484-5 standard protocol.


An identification tool to identify, manage and track assets.

Bathtub Curve

Visual tool that shows the rate of failure of a product over time.

Bill of Materials

A list of components that make up a specific asset.


When equipment has failed and is unable to function in any way.

Building Automation System (BAS)

A centralized network of a building that connects software with hardware. It monitors and controls the environment by uniting electricity, lighting, plumbing, HVAC, the water supply and drainage systems, all at a single control center.


To request the help of a tradesperson to an organization to perform a maintenance activity


Certification exam – the most popular credential for knowledge validation related to reliability, maintenance and asset management.


An asset’s subassembly. A part that is removable and can be replaced with another.

Computerized Maintenance Management Software

A platform that gives you all of the tools and insights you need to manage your maintenance department.

Condition Monitoring

Specialized equipment is used to evaluate the condition of an asset.

Condition-Based Maintenance (CBM)

A maintenance strategy that requires active monitoring of equipment. Depends on real-time information that indicates a decrease in equipment performance.

Conditional Probability of Failure

The percentage possibility that an asset will fail in a certain age interval.

Conveyor System

Used to physically move materials from one point to another, a collection of mechanical parts acting as a movable belt.

Corrective Maintenance

Maintenance performed to correct an occured failure. This may include to restore, repair or replace parts.


Also called a tradesperson. A trained maintenance technician.

Critical Control Point

A moment in the process of production where human error or mechanical failure could cause contamination of food. This could lead to customers getting sick or harm to the business’ reputation.


Based on assessment criteria, the priority rank of a failure mode.


The practice of keeping sensitive information and critical systems safe from digital attacks.


A potential failure that will probably require maintenance attention sometime in the future, but that is not currently a hinderance to its operations.

Design Failure Mode and Effects Analysis (DFMEA)

A process that helps organizations to find and repair design failures.

Deskless Workforce

The individuals in the workforce whose jobs don’t require them to work from a desk.

Discard Task

The disposal or removal of parts


The time that equipment is out of service because of equipment failure. The equipment is not used, but is available.

Economic Life

The amount of time that an asset is expected to remain operational before it would be cheaper to replace rather than maintaing it.

Emergency Maintenance Task

A maintenance task done to avoid and avert a sudden environmental or safety hazard or correct a failure that will significantly impact the business economically.

Engineering Change Notice (ENC)

A document that starts a process of making corrections or changes during the lifecycle of a product.

Engineering Change Order (ECO)

Same as an ENC: A document that starts a process of making corrections or changes during the lifecycle of a product.

Engineering Change Request (ECR)

A paper or electronic message that can be submitted to the management of an organization to either make an improvement to a product or solve an issue.

Engineering Work Order (EWO)

A document used to initiate an engineering modification, design activity or investigation to a piece of equipment.

Enterprise Resource Planning Software (ERP)

Software that assist organizations in managing all their professional processes and procedures more efficiently.

Environmental Consequences

The breach of any known environmental regulations or standards by the use of cerain equipment or the failure thereof.

Equipment Depreciation

A measurement of how much value a piece of equipment loses each year.

Estimated Plant Replacement Value

The cost estimated of actions required to replace a current asset with a new asset that is capable of producing the same quality and quantity of output.

Expert System

A software-based system that decides or evaluates choices established within the software. Often used for fault diagnosis.

Facility Condition Assessment

An assessment that observes a specific organization to monitor its health and predict maintenance work to keep it performing optimally.

Facility Management

The effective coordination of an organization’s assets, physical buildings and systems.

Facility Management Sustainability

The ability to meet the present needs of an organization, without compromising future generations’ ability to meet their needs.


When a piece of machinery or equipment is incapable of performing one or more of its intended functions.

Failure Code

A code entred into a CMMS when a failure have occured which then gives the cause of the failure.

Failure Effect

A description of the events that have occured after the initial main failure.

Failure Finding Interval

The frequency which a Failure Finding Task is conducted.

Failure Finding Task

Routine maintenance task, usually a testing task or inspection, to determine whether a piece of equipment has failed or to look for hidden failures.

Failure Mode

An event that cause a failure.

Failure Pattern

The correlations between an item’s age and the conditional probability of failure.

Failure Reporting, Analysis & Corrective Action System (FRACAS)

A process, consisting of 3 steps, used as a tool to achieve maintainability and reliability of military equipment systems.

Fault Tree Analysis

A visual representation of the way that a problem have occurred and the potential culprits that caused the main failure.

FDA validation

Guidance that is defined as the “collection and evaluation of data, from the process design stage through commercial production, which establishes scientific evidence that a process is capable of consistently delivering quality product.” (FDA, 2011)

Five Why’s

A technique used by maintenance teams to get to the root of a problem.

FiveS (5S)

5S is a set of principles originating from Toyota Production System, which intends to put a workplace into efficient order.

Fixed Asset

The items that belong to an organization that stay in one location during the organization’s operations.

Fleet Management

The management of vans, trucks and cars or any type of commercial vehicle.

Forward Workload

All backlog work or work that is predicted to become backlog work sometime in the future.


What a piece of equipment or machinery is required to do. Also, the level of performance the owner of such an asset expects of it when it does perform its function.

Gantt Chart

A bar type chart that shows the sequence and duration of scheduled activities.


Also called ‘Start-line’ and used to describe mobile equipment – equipment or machinery that is available but not currently used is usually parked on the Go-line.

Government Accounting Standards Board (GASB) 34

Accounting standards that requires government bodies to report what the value of their capital assets are on their financial statements.

Hazard Analysis Critical Control Point (HACCP)

A preventive, systematic program that aims to manage food quality and safety.


A structured process that aims to identify equipment modifications and safety devices proactively to avoid an environmental or safety incident that results from equipment failure.

Hidden Failure

A type of failure that is not obvious to the maintenance or operations team during normal operations / circumstances.

Idle Time

The accumulation of time spent on waiting to use operational equipment or the waste of employee time due to a lack of work.

Industrial Internet of Things (IIoT)

A set of security risks to a organization that does manufacturing.

Infant Morality

The relatively high conditional chance of failure when an item have just returned to service.

Inherent Reliability

Assuming compliance to flawless equipment maintenance strategies, a measure of an item’s reliability in its current operating context.


Any activity done to determine the condition of equipment, tools, materials and labor.


The process or act of uniting different software platforms for optimized performance.

Inventory Accounting

Keeps track of current inventory items’ value and the changes that takes place when consumables are consumed or when new items arrive.

Inventory Control

The management process of a company’s warehouse inventory levels. Also known as stock control.

Inventory Level(s)

The number of products that one should have in a fulfillment center(s) at any time.

Inventory Management

The tracking of items from the time of purchase to its time of use.

ISO 41001:2018

Facility Management standards that help organizations be more reliable and efficient. Its main aim is to optimize facility management and encourage consistency and sustainability.

No maintenance definitions available.


Means: “change for the better”. Applicable to continuous improvement philosophies in organizations.

Key Performance Indicators (KPI’s)

Used to track performance in several areas over time and indicate when an organization is operating inside or outside of acceptable levels. Using KPIs will help you rank assets criticality and create a maintenance strategy that will optimize asset performance and reduce costs and risks.

Leak Detection & Repair (LDAR)

Refers to EPA rules and its designed to aid the reduction of volatile organic compounds (VOC) en volatile hazardous air pollutants (VHAP).

Lean Maintenance

A Maintenance philosophy that is proactive in nature and strives to promote reliability as effectively as possible.

Level of Repair Analysis (LORA)

A process to establish where and when an asset should be repaired.

Life Cycle Costing

A process of assessing the total ownership, maintenance and operation costs of a piece of equipment during its life.

Lights-Out Manufacturing

A philosophy that is not dependant on human labor. Facilities using this philosophy are known as ‘dark factories’.

Logistic Support Analysis (LSA)

A philosophy to determine the quanitity and type of logistic support needed for a system over its whole lifecycle.


The detailed implementation and organization of a complex operation.

Machine Integration

The automation of a machine through a computer control software/hardware combination.

Machine Learning

The application of artificial intelligence (AI) that gives systems the capability to automatically learn from experience without being programmed explicitly.


The level of effort exerted into maintenance activities to maintain assets or equipment.


Activities performed to on assets to ensure the assets keeps on performing as expected or to repair the assets.

Maintenance Planning

A process of establishing what maintenance work should be completed and how it should be completed.

Maintenance Policy

A statement of priciple that is intended to be a guide to Maintenance Management and their desicion making.

Maintenance Schedule

A list of maintenance tasks, that have been planned ahead, that should be performed during a specific period of time. These tasks have pre-decided start times and durations.

Maintenance Strategy

A long-term plan, encompassing all aspects of maintenance management that establishes the direction for maintenance management, and specific plans for achieving a optimal future state for maintenance functions.

Maintenance Technician

A person who does general maintenance on equipment and who has the responsibility of keeping a facility up and running.

Maintenance, Repairs and Operations (MRO)

Refers to any process or equipment used to maintain a facility and its daily operations.

Mean Time Between Failures (MTBF)

A measurement of the reliability of equipment. Also equal to the total of equipment uptime in a certain period, divided by tht amount of failures in that period.

Mean Time To Repair (MTTR)

A measurement of maintainability. Equal to the total of equipment downtime, divided by the number of failures in a specific time period.

Metasys integration

A building automation system that integrates lighting, fire systems, HVAC, security, and specialty systems to optimize productivity.

Microsoft Azure Web Hosting (AWS)

A service platform which allows publishing Web apps running on different frameworks and written in multiple programming languages, including Microsoft original ones and third party ones.

Model Work Order

A work order that is stored in a CMMS and contains all the crucial information that is required to perform a maintenance activity.


Any activity done on an asset that increases its capability to perform its functions.

MRO cycle counting

Identifies inconsistencies in inventory levels and corrects inventory numbers before the items are recalled for equipment repair.

MRO parts management

Maintenance Repair and Operations. It includes all of the activities used to keep a facility (and machinery found inside it) in peak operating condition.

MRO supply chain

An acronym used in the practice of Supply Chain Management to describe a set of operations and activities related to the facility maintenance.

National Institute of Standards and Technology (NIST)

A non-regulatory agency and physical sciences laboratory of the United States Department of Commerce. Its goal is to promote creativity and industrial competitiveness.

Niagara integration

An advanced software infrastructure that adresses the complications of forming device-to-enterprise applications.

No Scheduled Maintenance

An equipment maintenance strategy where there is no routine maintenance tasks carried out on equipment.

Non-Destructive Testing (NDT)

Testing of equipment to detect abnormalities in electrical, physical or chemical functions but that does not destroy the equipment.

Non-Operational Consequences

If the only impact of a failure is the direct cost of the repair, a failure has non-operational consequences.

Non-routine Maintenance

A maintenance task that is not done regularly and according to a pre-determined frequency.

Occupational Safety and Health Administration (OSHA)

An act of 1970 which was created to ensure a healthful and safe working environment for workers by determining and enforcing standards and by providing outreach, training, assistance and education.

On-Demand Facilities Management

A special subdivison of a contractor, outside of the organization, focused on delivering support and services for facilities management in unusual circumstances.

OpenBlue integration

A scalable and flexible platform that complies data, stores it, and then standardizes it.

Operating Context

The operational environment within which an asset operates.

Operating Hours

The amount of time that a piece of equipment is physically operating.

Operational Consequences

If a failure has a direct adverse impact on operational capability.

Operational Efficiency

The output from an asset produced in a given time period divided by the output that could have been produced in that period, had it produced at its true capacity.


Related to power generation, also called a shutdown.

Overall Equipment Effectiveness (OEE) Software

A best-practice manufacturing productivity measure. Focused on the performance of manufacturing processes, quality of the final products, and asset availability to create an OEE score.


An advanced investigation and restoration of an asset to a prefrable condition.

Pen and Paper System

Manual maintenance management systems that are often very unorganized.

Piping & Instrumentation Diagram (P&ID)

A picture of the piping, controls and instruments for machinery in the process industry.


A Building or factory where goods are manufactured.

Plant Engineering

A function of specific staff memebers whose sole responsibility is to ensure that maintenance strategies are efficient.

Power BI,

A collection of software services, connectors, and apps that work together to turn unrelated data sources into visually immersive, coherent, and interactive insights.

Predictive Maintenance

Predictive maintenance techniques are designed to help determine the condition of in-service equipment in order to predict when maintenance should be performed.

Prescriptive Maintenance

A maintenance strategy that compiles and analyzes data about machinery condition to render tailored recommendations and outcomes to reduce operational risks.

Pressure Sensor

A device to measure and identify pressure. Pressure is the amount of force exerted over an area.

Preventive Maintenance

Routine maintenance, done consistently, to prevent equipment from failing. In other words, maintenance is done before the equipment has failed, and while it is still in operational condition.


The importance of a task compared to other tasks. Used in work order scheduling.

Proactive Maintenance

Any tasks done to prevent or predict equipment failures.

Process Failure Modes and Effects Analysis (PFMEA)

An analytical process utilized by businesses to find and identify possible process failures.

Production Efficiency

A measurement that identifies the environment in which goods, at the lowest possible unit cost, can be produced.

Programmable Logic Controller (PLC)

A piece of equipement that controls a computer system in an industrial organization.

Protective Device

Devices and equipment designed to reduce or eliminate the consequences of equipment failure.

Purchase Order

A commercial transaction document that identifies the type, price and quantity for a product or service.

Purchase Requisition

The main document used by user departments that authorises the purchase of specific supplies, equipment materials, parts or services from suppliers.

Quality Rate

The amount of output from a process or equipment which satifies the required product quality standards. Normally given as a percentage.

Ready Line

Used when talking about mobile equipment. Equipment that is available, but not used is generally parked on the Ready Line.


The ability of an asset to perform its originally intended functions.

Reliability Centered Maintenance (RCM)

A maintenance method that involves using the best strategies to keep equipment running.

Reliability Engineer

A professional that is in charge of managing and identifying asset reliability risks, and then ensuring those risks are reduced.

Renewable Energy

Any type of energy that is sourced from a naturally renewable source.


Any task that returns the function of an asset that has undergone failure to a level of operations equal to, or greater than, its specific functions.


Any task that returns the function of an asset that has undergone failure to a level of operations equal to, or greater than, its specific functions.

Return on Investment

The ratio between net income and investment.


The potential for the fulfilment of negative, unwanted results of an event.

Root Cause Analysis

A methodical process of recognizing the origin of an incident.


A rotable component is one that, when a failure has occured, or is prone to fail, is taken off from the asset and a replacement part is installed in its place.

Routine Maintenance Task

A maintenance task that is executed at a regular, predetermined interval.


Doing zero preventive or planned asset maintenance and letting the equipment run until it fails.

Scheduled Discard Task

Used to replace a particular part of a machine, irrespective of its performance capacity, at specific, scheduled time slots.

Scheduled Maintenance

Maintenance work that is included in the Maintenance Schedule or that was planned.

Scheduled Operating Time

The time that an asset is expected to operate according to a production schedule.

Scheduled Restoration Task

This type of task requires the maintenance manager to examine equipment thoroughly, as a regular activity, to establish the condition of the machinery.

Scheduled Work Order

A planned work order that’s included in a Maintenance Schedule.

Secondary Damage

Extra damage to equipment, beyond the original failure mode, that happens as a consequence of the original failure mode.

Secondary Function

The second function required of an asset – typically not connected with the reason for getting the asset, but now that the asset was acquired, the asset is now required to have this functionality.


The state of being free from threat or danger.

Sensor Integration

The art of processing information from a number of sensors with the goal to replicate a physical environment or encourage intelligence to control a phenomenon with improved precision and reliability.

Serpentine Belt

Used to drive a number of components at the same time, making it crucial that they remain in proper shape.


A period of time that equipment is not in service.

Shutdown Maintenance

Maintenance that is done only when equipment is shut down.

Single-Minute Exchange of Dies (SMED)

A process that aims to reduce the time it takes to complete equipment changeovers.

Standard Operating Procedure (SOP)

A document that describes steps to do something in a concise and clear way.

Standing Work Order

A work order that is kept open either for a pre-determined period of time or indefinitely with the goal of collecting labor hours.

Straight Line Depreciation

The decrease of an asset’s value is referred to as depreciation. It can also be the allocation of a asset’s original price over a number of years in an accounting system.

Supply Chain Logistics

The management of multiple processes, such as transportation, distributors and warehouses neccessary to deliver a final product.

Supply Chain Management

The process that gives direction to services, goods, money and information from initial acquisition to final delivery.

Takt Time

A modern term meaning the production time available divided by the demand by customers.


The application of financial, managerial, engineering and other skills to increase efficiency of, and prolong the life of machinery and equipment.

Theory of Constraints

A thoery that focuses on what holds back a goal in manufacturing and what motivates a team to make crucial changes to re-energize progress.


The process of constantly evaluating the state of equipment through the analysis and measurement of heat.

Third-Party Logistics (3PL)

When a company outside if the organization manages the receiving, storing, packing and shipping of products from a warehouse to customers.

Ticket Fare Evasion

When a group of people or an individual don’t pay a ticket.

Timing Belt

Has the intention of keeping a number of moving parts rotating in tandem. Also known as cog belts or synchronous belts.

Total Productive Maintenance (TPM)

A organization-wide equipment management program that emphasizes involvement of production operators in maintenance of equipment.


The process of tracking the condition of machinery through analysing the properties of its lubricating and other oils.

Unique Identification (UID)

A neccessary asset identification program that was given by the US Department of Defense.

Unplanned Maintenance

Any maintenance task which was not planned ahead of time and was not included in the maintenance schedule.

Unscheduled Maintenance

Maintenance work that was not included in the maintenance schedule.


The time which a piece of machinery is working as it should and performing its expected function(s).

Usage-based Maintenance (UBM)

A meter-based preventive maintenance. A trigger for UBM is when a certain machine or system goes beyond a certain usage threshold.

Useful Life

The maximum amount of time that equipment can be used before it starts to rapidly get maintenance issues and fail.

Utility management

A understanding how different sources of energy, water usage and watse metrics influences an organization.


The amount of time that machinery is operating. Calculated by dividing machinery operating hours by its available hours.


The most popular and common type of driver belt in machines that operate in the industrial industry. Has a V-shaped cross section.

Value engineering

A system-based approach of analyzing and assessing a new asset’s user requirements and ensure the new asset’s requirements are not exceeded, but met.

Vibration sensor

A device that measure the frequency and intensity of vibration in a machine or system.

Warehouse Automation

The people, hardware, software, and processes needed to automate warehouse tasks to so improve accuracy and efficiency.

Warehouse Logistics

The programs, people and processes needed to keep goods moving around and in a warehouse.

Warehouse Racking

The process of configuration, shelves and location of physical assets needed to keep inventory items.

Work order Master

With Work Order Master permission, you can manage, create and fulfill work orders. You can also give full premission to the individual work orders.

Work Order Template

A document that helps maintenance managers save time and ensure consistent and complete information is collected.

Work Request

The primary document to initiate a maintenance task, usually done by user departments.


The amount of work hours needed to do specific maintenance tasks.

No maintenance definitions available.

No maintenance definitions available.

No maintenance definitions available.