OPER10500A
Operations Management
Design of Work Systems
© DEPARTMENT OF LOGISTICS AND OPERATIONS MANAGEMENT, 2021
Conceptual Map
Time Study: Calculating NT and ST
Observed time (OT)
Performance rating (PR)
Normal time (NT)
Allowance factor (AF)
(as % of task time)
Standard Time (ST)
NT = OT x PR / 100
ST = NT x (1 + AF)
Example
Casing Sausages
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100%
