Industrial engineering: What does a comprehensive time study typically involve before establishing a reliable standard time?

Introduction / Context:
Time study is a cornerstone of work measurement. It establishes a fair and achievable standard time by observing work, analysing elements, and applying ratings and allowances. A narrow approach risks inaccurate standards.

Given Data / Assumptions:

• A defined repetitive operation suitable for stop-watch study.
• Competent, trained operator under normal working conditions.
• Use of standard rating and allowance practices.

Concept / Approach:
A robust time study includes: gathering contextual information (method, tools, layout), element breakdown for clarity, direct timing of several cycles, performance rating to convert observed to normal time, and allowances to cover fatigue, personal needs, and delays.

Step-by-Step Solution:

Verification / Alternative check:
Standard IE texts (work measurement) prescribe exactly these steps; omitting any reduces validity.

Why Other Options Are Wrong:
Options (a), (b), and (c) alone are incomplete; the correct practice is all combined.“Only rating” without observation is impossible and invalid.

Common Pitfalls:
Not stabilising the method before study; too few cycles; ignoring allowances; poor element definition.

Final Answer:

All of the above