Method Study

Method study improves the way a task is done before measuring how long it should take.

Key formulas & points

Skim these first — then read the full notes below.

  • Select job → record → examine → develop → install
  • Question sheet: why, what, where, when, who, how
  • Eliminate combine rearrange simplify (ECRS)

Topic details

Introduction

In Indian B.Tech Industrial Engineering courses, method study is taught as the first productivity lever. Groover and Buffa both emphasise that poor method design causes chronic waste even when workers are skilled.

Key relations & formulas

Formulas (Indian textbook notation)

  • processchart:operation,transport,inspection,delay,storageprocess chart: operation, transport, inspection, delay, storage

Formulas (Indian textbook notation)

  • flowprocesschart:manmaterialcombinedflow process chart: man-material combined

Formulas (Indian textbook notation)

  • efficiency=standardtimeobservedtime×100efficiency = standard \frac{time}{observed} time \times 100%

Notation and sign conventions

Relation 1 —
processchart:operation,transport,inspection,delay,storageprocess chart: operation, transport, inspection, delay, storage

Formulas (Indian textbook notation)

  • processchart:operation,transport,inspection,delay,storageprocess chart: operation, transport, inspection, delay, storage
Write this relation with symbols exactly as in Industrial Engineering & Management — O.P. Khanna before substituting numbers. Examiners award partial marks for a correct setup even when arithmetic slips.
Relation 2 —
flowprocesschart:manmaterialcombinedflow process chart: man-material combined

Formulas (Indian textbook notation)

  • flowprocesschart:manmaterialcombinedflow process chart: man-material combined
Write this relation with symbols exactly as in Industrial Engineering & Management — O.P. Khanna before substituting numbers. Examiners award partial marks for a correct setup even when arithmetic slips.
Relation 3 —
efficiency=standardtimeobservedtime×100efficiency = standard \frac{time}{observed} time \times 100%

Formulas (Indian textbook notation)

  • efficiency=standardtimeobservedtime×100efficiency = standard \frac{time}{observed} time \times 100%
Write this relation with symbols exactly as in Industrial Engineering & Management — O.P. Khanna before substituting numbers. Examiners award partial marks for a correct setup even when arithmetic slips.

Concept in depth

The classical approach is to map the present method using operation and flow process charts, challenge every activity through 5W1H questioning, and redesign using ECRS. Mahajan-style exam answers score better when you explicitly separate value-adding and non-value-adding motions. Chase-style operations thinking further links method quality to downstream capacity and lead time.

Assumptions and validity limits

State assumptions explicitly before using any relation for method study — steady state, uniform properties, linear elastic material, ideal gas, incompressible flow, etc., as applicable.
Wrong assumptions invalidate the entire solution even when the formula is correct. In Work Study viva and GATE descriptive questions, listing valid assumptions often earns separate marks.

Step-by-step problem approach

1. Read the question and list given data with SI units (common in Work Study papers).
2. Draw a neat labelled diagram where applicable — examiners in Indian universities award diagram marks even when arithmetic slips.
3. Identify which relation from this topic applies to method study.
4. Use equation 1:
processchart:operation,transport,inspection,delay,storageprocess chart: operation, transport, inspection, delay, storage
.
5. Use equation 2:
flowprocesschart:manmaterialcombinedflow process chart: man-material combined
.
6. Substitute values, compute, and verify units and sign (direction).
7. State conclusion in one line — e.g. safe/unsafe, stable/unstable, feasible/infeasible.

Applications & exam relevance

Method Study appears in line balancing and productivity. In Indian industrial curricula this topic is tested because it connects theory to method study and time standards.
GATE and semester exams often combine method study with earlier units — revise prerequisites before attempting mixed problems.
Industry interview panels sometimes ask: "Where did you use method study?" — answer with a lab, mini-project, or plant visit example if possible.

Common mistakes in exams

Students often jump to time standards without first simplifying the method. Another common mistake is writing chart symbols incorrectly (especially delay vs storage), which costs step marks.

Quick revision checklist

Before attempting method study problems, confirm you can:
1. Select job → record → examine → develop → install
2. Question sheet: why, what, where, when, who, how
3. Eliminate combine rearrange simplify (ECRS)
Revise the solved examples in Industrial Engineering & Management — O.P. Khanna and one previous-year GATE or university paper for this unit.

Worked examples

Try the problem first — open the solution when you are ready to check.

Method efficiency quick check

Problem

Observed time for old method is 8.5 min and for improved method is 7.2 min. Compute method efficiency gain percentage.

Solution

Efficiency gain = ((8.5 - 7.2) / 8.5) x 100 = 15.29%. Report that the redesigned method gives about 15.3% productivity improvement before any rating/allowance adjustment.

Conceptual check — Method Study

Problem

In a Work Study semester or GATE paper you are asked: "State the main assumption, the governing relation, and one practical consequence of method study." What should a complete answer include?

📖 Standard books (India)

  • Industrial Engineering & ManagementO.P. Khanna

    Read: Syllabus unit

    Work study, PPC, and OR basics