Enter the initial lumens and the maintained lumens into the calculator to determine the maintenance factor for lighting systems. The maintenance factor is a measure of the decrease in light output over time due to dirt accumulation and lamp lumen depreciation.
Maintenance Factor Formula
The following formula is used to calculate the maintenance factor:
MF = ML / IL
Variables:
- MF is the maintenance factor
- ML is the maintained lumens (lm)
- IL is the initial lumens (lm)
To calculate the maintenance factor, divide the maintained lumens by the initial lumens. The result is a ratio that indicates the performance of a lighting system after a certain period of use compared to its initial performance.
What is a Maintenance Factor?
The maintenance factor is a coefficient used in lighting design to account for the reduction in light output of a lighting installation over time. It considers factors such as lamp lumen depreciation, dirt accumulation on the luminaire and room surfaces, and maintenance practices. A higher maintenance factor indicates better light maintenance over time.
How to Calculate Maintenance Factor?
The following steps outline how to calculate the Maintenance Factor.
- First, determine the initial lumens (IL) of the lighting system.
- Next, determine the maintained lumens (ML) after a certain period of use.
- Next, gather the formula from above = MF = ML / IL.
- Finally, calculate the Maintenance Factor (MF).
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem:
Use the following variables as an example problem to test your knowledge.
initial lumens (IL) = 15000 lm
maintained lumens (ML) = 12000 lm
