A recent blog post featured the concept of TAKT time--the "pace of production" required to meet your customer's expectation. As you may recall, it is calculated as follows: Available time in seconds divided by the total number of specimens = TAKT time.
This blog article builds on the usefulness of TAKT time (the pace of production) in planning your laboratory resources.
Planned production time, by definition, is calculated by multiplying your TAKT time by 80%. If you have planned your production resources around this number, it will provide you a bit of a margin, when operational problem occur. (Note—Michael Rother in his book Toyota Kata suggests shortening the distance between TAKT and Planned Production time as a target condition that helps teams continuously improve their work processes.)
Cycle time is the sum of time it takes an operator to complete all of his/her assigned work tasks one time. In order to meet your customer's expectation, operator cycle times must be less than your planned cycle time or TAKT time. If his/her tasks take longer than TAKT, you will need to balance your operational line in one of three ways in order to meet nursing and physician specifications. In order of priority, here are some actions you could test:
Move some tasks to another value adding operator who's operating well below TAKT,
Add more value adding operators, or
Add an additional work cell.
Another use of TAKT time is the ability to determine the required number of operators within a work cell. It can be used for single piece flow situations and for small batch situations alike. Here are the examples:
Single piece flow measurements:
Customer TAKT was calculated at 72 second
Operator cycle time to produce results on one specimen = 240 seconds
Required number of operators = 240 divided by 72 = 3.33 FTE or 4 value-adding operators-a seasoned lean manager would Kaizen the work cell to eliminate non-value adding work so the cell could be staffed successfully with 3 value-adding operators.
Batch mode measurements:
Customer TAKT time was calculated at 50.7 seconds
Operator cycle time takes, on average, 15 minutes, or 900 second. The value-adding operator is moving among five analyzers and four computer stations.
The batch size averages 20 specimens per cycle at peak morning run.
Required number of operators = 900 seconds divided by 20 specimens per cycle divided by 50.7 seconds (TAKT) = .88 FTEs or 1 value-adding operator.
Today's discussion about TAKT time (customer expectation), operator cycle time, line balancing, and being able to determine the required number of operators for any process, places knowledge and control into the hands of practicing laboratory administrators, managers, supervisors, and lead technologists.
Your thoughts, questions, and experience with the use of these tools would be invaluable to the blog readership and me. I welcome your comments.