Touch Time and Cycle Time

Touch Time and Cycle Time in Six Sigma Black Belt Measure Phase

Understanding Touch Time and Cycle Time

Touch Time and Cycle Time are fundamental concepts in the Measure phase of Six Sigma that help organizations understand process efficiency and identify improvement opportunities.

What is Touch Time?

Touch Time (also called Processing Time or Value-Added Time) refers to the actual time spent actively working on a product or service. It is the time during which value is being created. Touch time only includes activities that directly contribute to transforming the input into the desired output.

Example: In a manufacturing process, if a worker spends 5 minutes assembling a component, that 5 minutes is touch time. Waiting for materials or inspecting the finished product after assembly would not be touch time.

What is Cycle Time?

Cycle Time is the total elapsed time from the start of a process until its completion. It includes all activities: value-added activities (touch time), waiting periods, transportation, inspections, and any other non-value-added activities.

Example: If a customer order takes 10 days from order placement to delivery, the cycle time is 10 days. If only 2 hours of that time involved actual processing (touch time), the remaining time represents non-value-added activities.

Why Are Touch Time and Cycle Time Important?

1. Process Efficiency Analysis: The ratio of touch time to cycle time reveals how efficiently a process operates. A high ratio indicates a lean process with minimal waste.

2. Identifying Waste: The gap between cycle time and touch time highlights non-value-added activities such as waiting, rework, and excessive handling.

3. Customer Value: Reducing cycle time while maintaining touch time can significantly improve customer satisfaction by delivering faster.

4. Cost Reduction: Eliminating non-value-added time reduces costs associated with inventory holding, storage, and labor.

5. Capacity Planning: Understanding these metrics helps organizations plan resources and schedule work more effectively.

6. Performance Metrics: These metrics serve as baseline measurements to track improvement initiatives.

How Touch Time and Cycle Time Work Together

The relationship between these two metrics can be expressed as:

Process Efficiency Ratio = Touch Time / Cycle Time × 100%

For example, if touch time is 2 hours and cycle time is 10 hours:

Process Efficiency = (2 / 10) × 100% = 20%

This means only 20% of the total time is spent on value-added activities, and 80% consists of non-value-added activities (waste).

Components Included in Each Metric

Touch Time Includes:

• Direct processing activities
• Manufacturing or service operations
• Assembly and inspection work that adds value
• Any activity the customer would pay for

Cycle Time Includes:

• All touch time
• Waiting time (queue time)
• Transportation time
• Setup time
• Rework time
• Inspection time (non-value-added)
• Administrative delays
• Any other elapsed time

How to Calculate These Metrics

Touch Time Calculation:

1. Identify all value-added activities in the process

2. Measure the time for each activity using time studies or work sampling

3. Sum the times for all value-added activities

Cycle Time Calculation:

1. Record the start time when work begins

2. Record the end time when the process is complete

3. Calculate: Cycle Time = End Time - Start Time

4. Alternatively, sum all activities (value-added and non-value-added)

Practical Example

Consider a pizza delivery process:

• Order received: 0 minutes
• Pizza preparation (touch time): 15 minutes
• Pizza baking (touch time): 12 minutes
• Packaging (touch time): 2 minutes
• Waiting for delivery driver: 8 minutes
• Delivery time: 20 minutes
• Order completed: Total cycle time = 57 minutes

Total Touch Time: 15 + 12 + 2 = 29 minutes

Total Cycle Time: 57 minutes

Process Efficiency: (29 / 57) × 100% = 50.88%

This indicates that about half the time is spent on value-added activities, and about half is waste.

Typical Values Across Industries

Different industries have varying efficiency ratios:

• Manufacturing: Typically 10-30% efficiency (significant setup and transport time)
• Service Industries: Typically 20-40% efficiency
• Healthcare: Often 15-25% efficiency (high administrative overhead)
• Lean Operations: Can achieve 50-80% or higher efficiency

Improvement Strategies

To Improve Process Efficiency:

1. Reduce Non-Value-Added Time: Eliminate waiting, transportation bottlenecks, and unnecessary inspections

2. Streamline Touch Time: Improve work methods to reduce actual processing time

3. Parallel Processing: Perform activities simultaneously where possible

4. Reduce Setup Time: Minimize changeover periods between tasks

5. Eliminate Rework: Improve quality to prevent defects requiring rework

6. Optimize Layout: Reduce transportation distances and waiting periods

Exam Tips: Answering Questions on Touch Time and Cycle Time

Key Definitions to Remember

Tip 1: Always remember that touch time is only value-added time. If you're unsure whether an activity counts, ask: "Would the customer pay for this directly?" If no, it's not touch time.

Tip 2: Cycle time always includes touch time plus all other activities. Never subtract touch time from cycle time; cycle time is always equal to or greater than touch time.

Common Exam Question Patterns

Question Type 1: Definition Questions

These ask you to define or distinguish between the two metrics. Always provide clear, concise definitions that emphasize the value-added nature of touch time and the comprehensive nature of cycle time.

Exam Tip: Use the phrase "value-added time" when defining touch time. Use "total elapsed time" when defining cycle time.

Question Type 2: Calculation Questions

These provide a scenario and ask you to calculate touch time, cycle time, or efficiency ratio.

Exam Tips:

• Read carefully to identify which activities are value-added
• Use the formula: Efficiency = (Touch Time / Cycle Time) × 100%
• Always show your work
• Include units in your answer (minutes, hours, or percentage)

Question Type 3: Scenario Analysis Questions

These present a process scenario and ask what improvements could be made or what the efficiency ratio suggests.

Exam Tips:

• Always calculate the efficiency ratio first
• Identify specific non-value-added activities to eliminate
• Suggest practical improvements aligned with Lean/Six Sigma principles
• Explain why your suggestion would improve efficiency

Common Mistakes to Avoid

Mistake 1: Confusing inspection time. General quality inspections are typically non-value-added (unless the customer specifically requires them).

Correction: Only include activities that directly transform the product/service in touch time.

Mistake 2: Forgetting to include all activities in cycle time calculation.

Correction: Make a complete list of all process steps, including waiting periods and transportation.

Mistake 3: Calculating efficiency as cycle time divided by touch time (inverted ratio).

Correction: Remember: Efficiency = Touch Time / Cycle Time, not the reverse.

Mistake 4: Assuming all measurement and inspection is non-value-added.

Correction: If customers require specific measurements or inspections, this may be value-added. Read the question carefully.

Problem-Solving Strategy for Exam Questions

Step 1: Read and Identify

Carefully read the scenario and identify each activity listed. Create a table with columns for Activity, Duration, and Value-Added (Yes/No).

Step 2: Classify Activities

For each activity, determine if it's value-added (touch time) or non-value-added. Ask: "Does this activity transform the product/service or directly support the customer's requirement?"

Step 3: Calculate

Sum touch time activities. Sum all activities for cycle time. Calculate the efficiency ratio if requested.

Step 4: Interpret and Explain

Discuss what the results mean. A low efficiency ratio indicates significant waste. A high efficiency ratio suggests a lean process.

Step 5: Recommend Improvements

If asked, suggest specific improvements to reduce non-value-added time, focusing on the largest opportunities.

Sample Exam Question and Solution

Question: A customer order process includes the following steps:

• Order entry by receptionist: 5 minutes
• Order verification: 3 minutes
• Waiting for production scheduling: 2 hours
• Production setup: 15 minutes
• Manufacturing: 45 minutes
• Quality inspection: 10 minutes
• Waiting for packaging materials: 1 hour
• Packaging: 8 minutes
• Shipping preparation: 5 minutes

Calculate the touch time, cycle time, and process efficiency ratio. What does this tell you about the process?

Solution:

Step 1: Identify Value-Added Activities (Touch Time):

• Manufacturing: 45 minutes ✓
• Packaging: 8 minutes ✓
• Order entry: 5 minutes ✓
• Production setup: 15 minutes (arguable, but typically considered non-value-added)

Touch Time = 45 + 8 + 5 = 58 minutes (or 73 minutes if including setup)

Step 2: Calculate Cycle Time:

5 + 3 + 120 + 15 + 45 + 10 + 60 + 8 + 5 = 271 minutes (or 4.5 hours)

Step 3: Calculate Efficiency:

Efficiency = (58 / 271) × 100% = 21.4%

Step 4: Interpretation:

Only 21.4% of the total time is spent on value-added activities. About 78.6% of the cycle time consists of waste (waiting for scheduling, waiting for materials, verification, inspection, and setup).

Step 5: Recommendations:

• Reduce waiting for production scheduling by improving schedule visibility (target: save 2 hours)
• Pre-position packaging materials to eliminate 1-hour wait (target: save 1 hour)
• Consider if quality inspection could be eliminated through better process control (target: save 10 minutes)

These improvements could reduce cycle time from 271 minutes to approximately 91 minutes, improving efficiency to about 64%.

Quick Reference Formulas

Touch Time / Cycle Time × 100% = Process Efficiency Percentage

Cycle Time - Touch Time = Non-Value-Added Time

Cycle Time = Touch Time + Waiting Time + Transportation Time + Other Non-Value-Added Time

Key Phrases for Exam Answers

When answering questions, use these key phrases to demonstrate understanding:

• "Touch time represents only the value-added processing activities..."
• "Cycle time is the total elapsed time from start to finish..."
• "The efficiency ratio shows that X% of time creates customer value..."
• "Significant non-value-added time indicates opportunities for process improvement..."
• "By reducing waiting and rework activities, we can improve cycle time without reducing touch time..."

Final Exam Preparation Tips

1. Practice Calculations: Work through multiple scenarios to become comfortable with the formulas.

2. Understand Context: Know that efficiency ratios vary by industry. 20% efficiency is excellent for some industries but poor for others.

3. Think Critically: Not all waiting time is obvious. Look for hidden delays and queuing.

4. Use Visuals: Draw process maps to help identify and classify activities.

5. Review DMAIC Connection: Understand how these metrics drive the Analyze phase improvements in Six Sigma projects.

6. Memorize Key Definitions: Be able to write a clear one-sentence definition of each term without hesitation.

7. Practice Explaining: Be ready to explain why reducing non-value-added time is important to overall business objectives.