Certified Facility Manager (CFM) Practice Exam

If a lamp has a life expectancy of 1,000 hours, what does this indicate?

1. It will last for exactly 2 weeks.

2. It will be replaced after 500 hours of use.

3. It is expected to last for approximately 1,000 hours before burning out.

4. It will only work for 1,000 minutes.

The correct answer is: It is expected to last for approximately 1,000 hours before burning out.

The correct answer indicates that a lamp with a life expectancy of 1,000 hours is anticipated to function effectively for roughly that duration before it is likely to burn out. Life expectancy provides a statistical average based on testing and usage, meaning that while some lamps may last longer and others may fail sooner, the general expectation is approximately 1,000 hours of use. This concept is crucial for facility management, as it helps in planning maintenance schedules, budgeting, and making informed decisions about inventory and replacements. In contrast to the other options, they either misinterpret the measurement of life expectancy or apply incorrect calculations and assumptions. For instance, stating that it will last for exactly 2 weeks miscalculates the time frame since 1,000 hours is equivalent to about 41.67 days of continuous use, not the 14 days suggested. Similarly, claiming that the lamp will be replaced after 500 hours contradicts the definition of life expectancy; lamps are typically not replaced until they reach their life expectancy unless failure occurs sooner. Lastly, the assertion that the lamp will only work for 1,000 minutes significantly underestimates its lifespan, as 1,000 hours is vastly longer than 1,000 minutes (which equates to about