Muda — 7 types of Waste
The 7 Deadly Wastes (muda)
as defined by Taiicho Ohno (Toyota executive, 1912-1990)
- Overproduction of things not demanded by actual customers
- Inventories awaiting further processing or consumption
- Unnecessary over-processing (for example, relying on inspections rather than designing the process to eliminate problems)
- Unnecessary motion of employees
- Unnecessary transport and handling of goods
- Waiting for an upstream process to deliver, or for a machine to finish processing, or for a supporting function to be completed, or for an interrupted worker to get back to work...
And a few more types of waste...
- Confusion — missing or misinformation. Confusing goals & metrics.
- Unsafe or unergonomic work conditions
- Underutilized human potential — skills, talents, and creativity
These types of waste are not the direct targets for continuous improvement.
They are symptoms. Your team needs to identify and eliminate the root causes.
Muda, Mura, and Muri
Muda = waste (in its many forms)
Muda waste is often accompanied or caused by...
Mura = unevenness, overburden, strain
Muri = demand that exceeds process and equipment capacities
“The most dangerous kind of waste is the waste we do not recognize.” ~ Shigeo Shingo
Office Examples of the 7 Types of Waste
|Type of Waste||Office Examples of Deadly Types of Waste|
|Defects||Data entry errors. Other types of order entry or invoice errors. Any error that gets passed downstream — only to be returned for correction or clarification. Engineering change orders. Design flaws. Employee turnover. Absenteeism.|
|Overproduction||Printing paperwork (that might change) before it is needed. Processing an order (that might change) before it is needed. Any processing that is done on a routine schedule — regardless of current demand.|
|Inventories||Purchasing or making things before they are needed (think office supplies, literature...). Things waiting in an (electronic or physical) In Box. Unread email. Any form of batch processing (e.g. transactions, reports...)|
|Over-processing||Relying on inspections, rather than designing the process to eliminate errors. Re-entering data into multiple information systems. Making extra copies. Generating unused reports. Expediting. Unnecessarily cumbersome processes (think financial statement period end close, expense reporting, the budget process...)|
|Human Motion||Walking to copier, printer, fax... Walking between offices. Central filing. Going on a "safari" to find missing information. Backtracking back & forth between computer screens.|
|Transportation & Handling||Movement of paperwork. Multiple hand-offs of electronic data. Approvals. Excessive email attachments. Distributing unnecessary cc copies to people who don't really need to know.|
|Waiting||Slow computer speed. Downtime (computer, fax, phone...). Waiting for approvals. Waiting for information from customer. Waiting for clarification or correction of work received from upstream process.|
|Confusion||Any missing or misinformation. Any goals or metrics that cause uncertainty about the right thing to do.|
|Unsafe or unergonomic||Office work conditions that cause carpel tunnel, eye fatigue, or chronic back pain, or conditions that compromise the health and productivity of workers in any way.|
|Underutilized human potential||Restricting employee's authority and responsibility to make routine decisions. Having highly paid staff do routine tasks that don't require their unique expertise. Not providing the business tools needed to perform and continuously improve each employee's assigned work. Not trusting your people to stop production to stop and fix a problem (jidoka). Not trusting your people to be responsible for the cleanliness, maintenance, and organization of their own work area. Not trusting people with a flat organization structure of largely self-directed teams. Not expecting (and measuring) every person to contribute to continuous improvement.|
Muda: Type one vs. type two
Waste can also be categorized as:
- Type one muda — adds no value and can be eliminated immediately. “That's embarrassing. Let's stop doing that.”
- Type two muda — adds no value, but is required for the way things are currently done
(e.g. inspection, paperwork, and all of the above types of deadly waste).
Also see training for Value Add Time in our lean dictionary.
User-defined types of waste
In the Systems2win Time Observation Worksheet Types of Waste column...
you can enter any of the above classic deadly types of waste, and you can also enter any user-defined subcategories that your team finds most useful for analyzing the unique types of waste found in YOUR process.
On the Systems2win Standard Work Combination Sheet template...
notice that the Value Add Pie Chart is comprised of:
- Walk time
- Wait time
- Work time split into:
- Value Add Time
- 7 user-defined types of lean waste
the titles for types of waste are user-defined —
so that your team can best analyze and eliminate the unique types of waste found in YOUR process
Sample Standard Work Combination Sheet
How to eliminate the 7 forms of waste
- Lean Objectives and Ideals
- The PDCA scientific method
- The Improvement Kata
- The Lean 4 Rules In Use
- Hansei: Reflect, Ponder, Think
- Kaizen and Lean Training home page
Systems2win Word and Excel templates
for process improvement
Eliminate deadly wastes with continuous improvement templates: