Time Study — Simulator · Tyshchenko Lean Academy

📌 What a time study is

A time study is a method for studying how time is spent by recording and measuring the duration of each action. It is done at the Gemba to collect real data on how long operations take.

Goal 1

Find out what the operator’s time is spent on

Goal 2

Spot the “time eaters” — where delays happen

Goal 3

Find spare time that can be used for improvement

Goal 4

Build a “feel for efficiency” and a “feel for time”

📏 How to run it

★ At least 10 measurements for a stable process. For an unstable one, 20+

1

Don’t warn the operator 5 minutes ahead. Behavior changes under observation

2

Record EVERYTHING — including pauses, looking for tools, and waiting

3

Discard the first measurement — the operator has only just noticed you

4

Anomaly = a value > mean + 20%. Record its cause separately

5

“Clean” mean = the mean without anomalies. That is the real cycle time of the process

📐 Key metrics

Cycle time (CT)

The “clean” mean cycle time. The basis for calculating productivity

Takt time (TT)

Available time ÷ demand. The target we work to

CT > TT

Bottleneck! The process can’t keep up with demand

CT ≤ TT

Fine. There is spare capacity, or it can be cut

🏭 Choose a scenario

An operator assembles a unit from 4 parts. Takt time = 45 sec. Goal: measure 10 cycles and decide whether the process fits the takt.

Takt: 45 sec Target measurements: 10

⏱ Stopwatch

00:00.00

Press START to begin measuring

Measurements: 0 / 10

Current lap —

#	Time (sec)	Diff. from mean	Status
Your measurements will appear here

📊 Practice case to analyze

A process engineer ran a time study of the “Fit the lid” operation in a packing area. Takt time = 38 sec. Below are 10 measurements. Analyze the table and answer the questions.

#	Time (sec)	Note
1	34	—
2	36	—
3	33	—
4	67	Spent 30 sec looking for a lid
5	35	—
6	37	—
7	34	—
8	72	Waited for the inspector
9	36	—
10	33	—

❓ Question 1: What is the mean of ALL 10 measurements?

34.7 sec

41.7 sec

38.0 sec

❓ Question 2: How many anomalous measurements are in the table?

0 — all normal

1 — only #4

2 — #4 and #8

❓ Question 3: What is the “clean” cycle time (without anomalies)?

34.75 sec

38.0 sec

41.7 sec

❓ Question 4: CT = 34.75 sec, takt time = 38 sec. Conclusion?

The process is a bottleneck — CT > TT

The process fits the takt with 3.25 sec to spare

CT = TT — a perfect balance

💡 KEY TAKEAWAY

Anomalies #4 and #8 revealed systemic problems — no organized place for lids and an unstructured inspection process. This isn’t the “human factor” — it’s systemic waste that is solved with 5S and standardization.