Understanding Predetermined Motion-Time Standards in Business Operations

Introduction

Efficiency in business operations is crucial for maintaining competitiveness. One of the widely used methodologies for optimizing productivity is Predetermined Motion-Time Standards (PMTS). PMTS is a work measurement technique that breaks down tasks into basic human movements and assigns standard time values to them. This article explores the fundamental concepts, applications, benefits, and limitations of PMTS, supported by examples and mathematical calculations.

The Foundation of PMTS

PMTS is built on the premise that human motions in a task can be analyzed and assigned predetermined time values. These time values help organizations establish accurate work standards, streamline operations, and optimize labor costs.

Key PMTS Systems

Several systems exist for implementing PMTS, including:

1. Methods-Time Measurement (MTM) – Analyzes motions at a micro level.
2. Maynard Operation Sequence Technique (MOST) – Focuses on common workplace motions.
3. Work Factor System – Categorizes work elements by difficulty.

Each of these systems allows businesses to quantify time for different activities without continuous stopwatch-based time studies.

Mathematical Formulation in PMTS

To understand PMTS in a structured manner, we need to analyze task time computation.

If an operation consists of multiple motions, the total time required, TT, can be calculated as:

$T = \sum_{i=1}^{n} (M_i \times C_i)$

Where:

• MiM_i is the motion element time (in TMU, Time Measurement Unit).
• CiC_i is the number of occurrences of that motion in a task.

For example, if a motion sequence consists of three motions with times 5 TMU, 10 TMU, and 15 TMU, appearing 3, 2, and 4 times respectively, the total time in TMU is:

$T = (5 \times 3) + (10 \times 2) + (15 \times 4) = 15 + 20 + 60 = 95 \text{ TMU}$

Converting TMU to seconds (where 1 TMU = 0.036 seconds):

$T_{seconds} = 95 \times 0.036 = 3.42 \text{ seconds}$

Application of PMTS in Business Operations

PMTS is applicable in various industries to standardize operations. Some key areas include:

Manufacturing

• Assembly line optimization
• Workstation balancing
• Productivity benchmarking

Retail and Logistics

• Order fulfillment timing
• Warehouse operations optimization
• Packaging efficiency

Healthcare and Service Industry

• Standardizing procedural times
• Reducing wait times in service industries
• Improving staff productivity

Benefits of PMTS

Benefit	Description
Accuracy	Eliminates guesswork in task time estimation
Labor Cost Control	Helps set labor budgets effectively
Efficiency Improvement	Identifies bottlenecks and reduces non-value-added activities
Consistency	Ensures uniform work standards across operations

Limitations and Challenges

Despite its advantages, PMTS has some challenges:

• Initial Setup Complexity: Implementing PMTS requires skilled personnel.
• Variability in Human Performance: PMTS does not account for fatigue or learning curves.
• Technological Changes: Automation can quickly make PMTS obsolete in some industries.

Example Calculation for Business Optimization

Assume a warehouse has an order fulfillment process with the following motion elements:

Motion	TMU per Motion	Occurrences per Order
Picking an item	10	3
Placing item in a bin	8	3
Labeling package	12	1
Moving to the next station	20	1

The total TMU per order is:

$T = (10 \times 3) + (8 \times 3) + (12 \times 1) + (20 \times 1) = 30 + 24 + 12 + 20 = 86 \text{ TMU}$

In seconds:

$T_{seconds} = 86 \times 0.036 = 3.096 \text{ seconds per order}$

By optimizing work design, businesses can reduce wasted motions and increase efficiency.

Conclusion

PMTS provides businesses with a structured approach to measure and enhance productivity. By breaking tasks into predetermined motion standards, companies can optimize workforce efficiency, reduce costs, and improve operational consistency. However, businesses must continuously adapt PMTS methodologies in response to changing technologies and work environments.