Definition
Ownership Maintenance (自主保全, jishu hozen) is the practice of having production operators — the people who use equipment every day — take ownership of basic equipment care through daily cleaning, inspection, and checking. The purpose is not to replace skilled maintenance technicians but to engage operators in early detection of small defects before they escalate into breakdowns and production stops.
Within Toyota’s 3 Pillar Activity, Ownership Maintenance is the second pillar, related to Machine/Equipment (設備) in the 4M management framework. While the concept is widely known in the TPM (Total Productive Maintenance) world as “autonomous maintenance,” Toyota’s use of “ownership” in the English name is deliberate — it emphasizes that operators are not just performing maintenance tasks under instruction but taking genuine ownership of their equipment’s condition.
Japanese Origin
自主 (jishu) means “self-directed, autonomous, voluntary.” 保全 (hozen) means “maintenance, preservation, upkeep.” Together: “self-directed maintenance” — maintenance performed out of ownership and initiative, not because someone told you to do it.
The term emphasizes the operator’s agency. This is not assigned maintenance work — it is the operator’s own recognition that the equipment is their responsibility and that its condition directly affects their ability to do good work safely.
Ownership Maintenance and Autonomous Maintenance
The Japanese term 自主保全 (jishu hozen) is the same in both cases. In the TPM (Total Productive Maintenance) tradition established by Seiichi Nakajima in the 1970s–80s, the standard English translation has been “autonomous maintenance” — one of TPM’s eight pillars. This translation emphasizes the autonomy of the activity: operators maintain equipment independently rather than depending entirely on the maintenance department.
Toyota uses the term “Ownership Maintenance” in English. The shift in language reflects a shift in emphasis. “Autonomous” describes the organizational structure — who does the work. “Ownership” describes the mindset — why they do it. An operator performing autonomous maintenance might be following a checklist because the TPM program requires it. An operator practicing ownership maintenance cares about their equipment because it is theirs — they notice changes, they feel responsible for its condition, and they take initiative when something is not right.
The underlying practices are the same: cleaning, inspecting, lubricating, tightening, detecting small defects early. But the word “ownership” sets a higher bar for what success looks like. A successful ownership maintenance practice is not one where all the checklists are completed — it is one where operators genuinely know their equipment and act on what they observe.
History at Toyota
Operator involvement in equipment care at Toyota predates the formal TPM framework. Toyota’s production system has always expected operators to take care of their equipment as a natural extension of taking care of their work. The logic is straightforward: an operator who understands their equipment’s normal condition can detect abnormalities early. Early detection prevents breakdowns. Preventing breakdowns enables just-in-time flow.
When the 3 Pillar Activity was formalized in the mid-2000s, Ownership Maintenance was codified as one of the three pillars alongside Standardized Work and Cutting Point Management. This formalization created structured evaluation criteria and certification levels (Bronze, Silver, Gold) that made it possible to assess and develop a group’s maintenance capability systematically rather than relying on individual supervisors’ judgment.
How It Actually Works
The Tag On / Tag Off System
The core practice is the “tag on / tag off” system. Operators inspect and clean their equipment and attach tags when they identify small defects (“tag on”). Group leaders then review the tags and make a plan for countermeasures (“tag off”), which may involve shop floor staff working on issues within their capability or escalating to maintenance specialists for more complex problems.
The physical tags create immediate visibility — you can see at a glance how many open defects exist on a piece of equipment. A machine covered in tags is a machine that needs attention, and that visibility creates urgency that a digital log does not.
Deep Cleaning
The deep cleaning practice goes beyond daily surface cleaning. Equipment covers are removed and the equipment is thoroughly inspected with specialist support. This provides operators with learning opportunities about the internal workings of their machines — understanding what is inside the equipment they operate every day. Deep cleaning events often uncover deterioration that is invisible during normal operation.
Daily Routine
Before starting production, the operator performs a brief check — typically 5-10 minutes — covering cleaning, visual inspection of key points, lubrication of specified points, and tightening of critical fasteners. Abnormalities are tagged and reported. The routine is documented as standardized work.
What Operators Detect
The intent is to leverage what only operators can know. Operators see and feel equipment conditions every day: a bearing that vibrates slightly more than usual, a sound that has changed, a surface that is wearing unevenly. This information exists only in the operators’ direct experience and does not show up in downtime data or maintenance reports until it becomes a visible failure.
Evaluation Within the 3 Pillar Activity
Ownership Maintenance has its own evaluation structure within the 3 Pillar certification system, consisting of 6 major categories and 10 scored items:
- Equipment 4S condition
- Shop floor self-maintenance execution
- Supervisor leadership of maintenance activities
- Human resource development for maintenance skills
- Sharing of results across areas
- Collaboration with dedicated maintenance departments
The supervisory leadership items are particularly important. Because Ownership Maintenance is not direct production work, managers must actively support it through allocating time, securing resources, and reinforcing its importance. Without management commitment, operators learn quickly that equipment care is secondary to production output — and the practice erodes.
Groups progress through Bronze (form established), Silver (improvement progressing), and Gold (results emerging) certification, assessed by qualified internal assessors.
Relationship to Professional Maintenance
Ownership Maintenance explicitly does not replace professional maintenance. The boundary is clear: operators handle daily cleaning, inspection, lubrication, and basic checks. Skilled maintenance technicians handle repairs, overhauls, precision work, and complex diagnostics.
The two functions collaborate. When operators identify defects through the tag system that exceed their capability, they escalate to maintenance. When maintenance performs repairs, they can share knowledge with operators about what to watch for in the future. The collaboration evaluation items in the 3 Pillar assessment explicitly check that this relationship is functioning — that operators and maintenance are working together, not in silos.
Common Mistakes
Not providing time for the activities. Ownership Maintenance requires time in the production schedule. If operators are loaded to 100% of takt time with production work, there is no time for equipment care. The activities will be skipped, and breakdowns will continue.
No response to operator-reported problems. If operators tag abnormalities and nothing happens — the maintenance department does not respond, tags accumulate, and nothing is fixed — operators learn that reporting is pointless and stop doing it. Fast response to tags is essential to sustaining the system.
Treating it as a checklist exercise. Ownership Maintenance requires operators to actually look at, touch, and understand their equipment — not just check boxes on a form. A completed checklist with unchecked equipment is worse than no checklist at all.
Lack of supervisory support. Because this is not direct production work, it requires active management reinforcement. If group leaders, assistant managers, and managers do not visibly participate in and prioritize maintenance activities, operators will deprioritize them in favor of output. The 3 Pillar evaluation specifically checks for supervisory involvement for this reason.
Attempting without 4S foundation. Within the 3 Pillar Activity, groups must achieve Gold certification in 4S + Shitsuke before beginning Ownership Maintenance. If the workplace lacks basic organization and cleanliness standards, adding maintenance routines on top creates unsustainable complexity.