Equipment utilization factor is expressed as
- AAvailable hours / Operating hours
- BDowntime / Operating hours
- COperating hours / Available hoursCorrect
- D(Available hours - Downtime) / Available hours
Solution
Concept
Equipment utilization factor in construction management
Formula
Utilization Factor = Operating Hours / Available Hours
Step-by-step solution
1. Define equipment utilization: ratio of productive operating time to the total time the equipment was available for operation. 2. Operating hours = time machine actually worked. 3. Available hours = total scheduled working hours minus maintenance/breakdown downtime. 4. Utilization factor = Operating hours / Available hours. 5. Therefore, option C expresses the factor correctly. Answer: C
Explanation
The Equipment Utilization Factor represents the proportion of available equipment time during which the machine is actively performing productive work. It is mathematically expressed as Operating Hours divided by Available Hours: Utilization Factor = Operating Hours / Available Hours.
Why the other options are wrong
A) Available hours / Operating hours is the inverse of utilization and would yield values greater than 1. B) Downtime / Operating hours measures failure or repair ratio. D) (Available hours - Downtime) / Available hours is equivalent to Operating hours / Available hours only if downtime is deducted from available rather than scheduled hours.
Shortcut
Utilization = Productive Operating Hours / Available Hours.
Common mistake
Inverting the ratio (Available hours / Operating hours) or confusing utilization with machine availability.
Correct answer: C) Operating hours / Available hours