Tuesday, February 8, 2011
Objective: To determine the standard time of an operation.
Equipment: Product to be assembled, tools for the operation, stopwatch, time
study form and table of allowance.
Procedure: 1. Divide the job into elements.
2. Conduct the stop watch time study and record the results in the
form provided. Record also the observed ratings.
3. If using continuous stop watch method, calculate the elemental
4. Calculate the number of observations required to achieve 95%
confidence level and ± 5% allowance error.
Where N = the number of readings to be determinedn = the number of readings in taken in preliminary study
x = the reading
5. Calculate the average rating.
6. Calculate the normal time.
7. Determine the allowance. (Table 1)
8. Calculate the standard time.
Allowance is the extra time added to the normal time to make the time standard practical and attainable.
There are 3 types of allowances:
1. Allowance for personal time.
The time an employee is allowed for personal things such as going to the bathroom, getting a drink and other operator-controlled reason for not working.
2. Fatigue allowance
The time an employee is allowed for recuperation from fatigue.
3. Delay allowance
The time given for unavoidable delays that are beyond the operator’ s control such as waiting for instructions or material, machine breakdown and maintenance.
Table 1 shows the allowance for assembly operation suggested by ILO (International Labor Organisation)