What Is MRO? Introduction to Maintenance Repairs and Operations

MRO—Maintenance, Repair, and Operations—is a frequently used acronym within the maintenance sector.

Maintenance professionals also sometimes refer to Maintenance, Repair, and Overhaul when using the term MRO. Organizations use the term to describe the various supplies used during operational processes that do not become part of product deliverables.

Examples of MRO items include:

  • Industrial Equipment (e.g., pumps, motors, belts)
  • Consumables (e.g., cleaning supplies, office supplies)
  • Maintenance Supplies (e.g., lubricants, gaskets, repair tools)

MRO can include hundreds of subcategories involving supply-chain materials.

Maintenance, Repair, and Operations

The global maintenance, repair, and operations market was valued at USD 254.05 Billion in 2021, and it is projected to be worth USD 291.32 Billion by 2027.

In other words, MRO’s impact on overall performance is massive.

“The increasing demand for enhanced organizational efficiency across industries is one of the key factors driving the growth of the market.”


Organizations rely on several types of assets to run smoothly, including facility structures, machinery, furniture, and technology systems. Many of these items require continuous maintenance efforts involving keeping assets in working condition alongside strong distributor relationships.

The objective of MRO is to ensure departments always have the materials they need to be effective. Keeping crucial MRO supplies on hand accomplishes organizational goals, including reducing downtime, increasing safety, extending equipment useful life, minimizing overstocks, and protecting customer deliveries.

Maintaining strong MRO directly impacts a company’s key performance indicators. These KPIs include: equipment downtime, maintenance backlogs and overtime, asset performance metrics, and operational metrics.

Modern Materials Handling Magazine reported that “For 94% of respondents, MRO is either extremely or somewhat important to their companies’ overall operations. Those who see MRO as ‘extremely’ important say it helps their firms maintain customer satisfaction, maintain continuous production, follow lean practices, and secure the ‘right parts for the first time, every time.’ Respondents that view MRO as ‘somewhat important’ say it helps to reduce downtime, manage preventative maintenance, and streamline their plants.”

To sum it up, the survey indicated that MRO is crucial to overall operations.

What Role Does MRO Play in Supply-Chain Management?

MRO expenses usually run “5 to 10 percent of the cost of goods sold (COGS),” as reported by Supply Chain Game Changer.

This is why many organizational leaders treat MRO as an afterthought. However, priorities soon change when a vital material’s absence stops production processes due to inoperable equipment.

The smallest missing supply—whether a missing tool, part, or chemical component—can derail assembly lines for hours. Depending on the industry, one hour of downtime can translate into hundreds of thousands of dollars in missed profits.

Late customer deliveries, employee idle time, and missed targets all translate to money lost unnecessarily. Not only does poor MRO management negatively impact supply chains, but it can also lead to safety hazards. In some instances, running out of a critical safety component can threaten employee well-being.

What Are MRO Products and Materials?

MRO products and materials are essential items and supplies that are used in the day-to-day maintenance, repair, and operations of industrial or manufacturing facilities. Examples include spare parts, safety equipment, or cleaning supplies. These products are not directly involved in the production process, but they are crucial for keeping operations running smoothly and maintaining the physical assets of a business.

MRO products are critical for maintaining a safe, efficient, and compliant work environment. They are typically managed through an organized inventory system to ensure that they are readily available when needed for maintenance, repair, or operational tasks.

What Are the Types of MRO?

As outlined by Thomasnet.com, industry experts typically divide MRO into four categories:

1. Production Equipment Maintenance and Repair

This category of MRO focuses on the maintenance of critical assets and systems so that production isn’t disrupted. Over time, frequently used machines experience wear and tear necessitating more frequent upkeep over time.

MRO activities related to production equipment include routine and emergency maintenance, purchase of condition-monitoring equipment, replacement parts inventory management, and supplier management. Switching to proactive maintenance strategies such as predictive and preventive maintenance help production facilities stay on top of maintenance and improve asset uptime, availability, and reliability.

2. Material Handling Equipment Maintenance and Repair

Material handling equipment includes different types of machinery, such as forklifts, storage systems, bulk containers, conveyor systems, robotic arms, and pallet positioners.

These items are essential for moving raw materials and components through production lines. They also help transport finished products to loading bays, where workers can ship them to customers. It’s crucial to ensure that material handling equipment remains operable to avoid idle time.

3. Infrastructure Maintenance and Repairs

Though not as immediately pressing, management must prioritize the upkeep of facility infrastructure. This type of maintenance includes cleaning services, lighting and HVAC systems servicing, pest control, grounds maintenance, and building maintenance.

4. Tools and Consumables

Finally, MRO includes hand tools and limited-use items needed to execute maintenance and repairs. Examples of MRO tools and consumables include power tools such as electric saws, hand tools such as pliers, PPEs, lubrication liquids, adhesives, welding rods, sandpaper, and office supplies. These items are usually small and can easily get lost in a large facility. They, therefore, need proper management too.

What Do MRO Professionals Do?

Different types of organizations have different MRO needs. Small businesses with relatively low MRO expenses—restaurants, resorts, private practices—typically entrust a general manager to oversee all aspects of MRO.

Alternatively, large organizations—warehouses, manufacturers, oil and gas companies—often divide responsibilities amongst a team of professionals to ensure operations run smoothly. Essential roles within high-volume MRO facilities include:

Procurement Officers

MRO departments often require dedicated MRO procurement personnel who have experience working with organizational items. They are responsible for assessing the suitability of suppliers, products, and services and negotiating contracts with suppliers. Additionally, they ensure businesses purchase high-quality and cost-efficient MRO products.

Supplier Relationship Managers

Large organizations often require a specific manager to maintain relationships with suppliers. Considering that businesses need raw materials to produce deliverables for customers, maintaining reliable supply chains is paramount to success.

Though some suppliers are undoubtedly more important than others, most businesses source supplies from various sources. Supplier relationship managers identify “mission-critical” MRO items and secure iron-clad purchase order arrangements to ensure their organizations always have the materials they need to stay in business.

Inventory Managers

Inventory managers are responsible for adequately stocking MRO items at all times. A large part of their responsibilities is overseeing the quantity levels of spare parts necessary for performing both preventive maintenance and corrective maintenance, as needed.

MRO inventory management is crucial to reducing unnecessary downtimes, delayed deliveries, and expedited shipping costs associated with emergency inventory orders.

Standards/Compliance Officer

Without proper controls, there’s always a risk of purchasing defective MRO items. In addition, companies must remain vigilant against procuring items from unauthorized suppliers who can’t guarantee quality control.  

This is where a compliance officer steps in. This person can ensure that all MRO items are secured following compliance regulations and that no illegal items are purchased.

Streamline Maintenance Repairs and Operations with CMMS

MRO management can be a daunting task. O&M managers need to consider several factors to manage material and supply levels efficiently.

This includes accounting for each asset within individual facilities, tracking inventory levels, and overseeing scheduled maintenance. However, with a proper MRO management system in place, your maintenance team will always have the right parts and tools at the right time.

The best way to streamline MRO management is with a computerized maintenance management system (CMMS) like MaintainX. The software enables department leaders to oversee assigned work orders in real-time, monitor MRO inventory levels, export data for suppliers, and generate cost reports.

MaintainX CMMS is compatible with desktops, tablets, and mobile devices.

author photo
Caroline Eisner

Caroline Eisner is a writer and editor with experience across the profit and nonprofit sectors, government, education, and financial organizations. She has held leadership positions in K16 institutions and has led large-scale digital projects, interactive websites, and a business writing consultancy.

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