When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?
The correct answer is A: Each transmitter that produces 20 percent or more of its MPE limit in areas where the total MPE limit is exceeded. When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of each transmitter that produces 20 percent or more of its MPE limit in areas where the total MPE limit is exceeded are responsible for mitigating over-exposure situations.
When multiple transmitters contribute to RF exposure, you must evaluate the total exposure. If the total exceeds MPE limits, then each transmitter contributing 20% or more of its own MPE limit is responsible for helping to reduce the exposure. This ensures that significant contributors share responsibility for compliance. Transmitters contributing less than 20% are considered minor contributors and aren't required to take action. This rule prevents any single operator from being solely responsible when multiple stations contribute to over-exposure.
Exam Tip
Multiple transmitter responsibility = 20% or more contribution. Remember: When multiple transmitters cause over-exposure, each transmitter contributing 20% or more of its MPE limit in areas where total limits are exceeded is responsible for mitigation.
Memory Aid
"**M**ultiple **T**ransmitter **R**esponsibility = **2**0% or **M**ore (think 'MTR = 20%+')"
Real-World Application
You operate at a site with three other stations. The total RF exposure exceeds MPE limits. Your station contributes 25% of its MPE limit, Station B contributes 30%, Station C contributes 15%, and Station D contributes 10%. You and Station B are responsible for mitigation (20% or more), while Stations C and D are not (less than 20%).
FCC Part 97.13Key Concepts
Why Other Options Are Wrong
Option B: Incorrect. Duty cycle alone doesn't determine responsibility. The key is whether the transmitter contributes 20% or more of its MPE limit in areas where total limits are exceeded.
Option C: Incorrect. Operating time doesn't determine responsibility. The 20% contribution rule applies, not operating time.
Option D: Incorrect. Not all transmitters are responsible - only those contributing 20% or more of their MPE limit in areas where total limits are exceeded.
题目解析
The correct answer is A: Each transmitter that produces 20 percent or more of its MPE limit in areas where the total MPE limit is exceeded. When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of each transmitter that produces 20 percent or more of its MPE limit in areas where the total MPE limit is exceeded are responsible for mitigating over-exposure situations. When multiple transmitters contribute to RF exposure, you must evaluate the total exposure. If the total exceeds MPE limits, then each transmitter contributing 20% or more of its own MPE limit is responsible for helping to reduce the exposure. This ensures that significant contributors share responsibility for compliance. Transmitters contributing less than 20% are considered minor contributors and aren't required to take action. This rule prevents any single operator from being solely responsible when multiple stations contribute to over-exposure.
考试技巧
Multiple transmitter responsibility = 20% or more contribution. Remember: When multiple transmitters cause over-exposure, each transmitter contributing 20% or more of its MPE limit in areas where total limits are exceeded is responsible for mitigation.
记忆口诀
**M**ultiple **T**ransmitter **R**esponsibility = **2**0% or **M**ore (think 'MTR = 20%+')
实际应用示例
You operate at a site with three other stations. The total RF exposure exceeds MPE limits. Your station contributes 25% of its MPE limit, Station B contributes 30%, Station C contributes 15%, and Station D contributes 10%. You and Station B are responsible for mitigation (20% or more), while Stations C and D are not (less than 20%).
错误选项分析
Option B: Incorrect. Duty cycle alone doesn't determine responsibility. The key is whether the transmitter contributes 20% or more of its MPE limit in areas where total limits are exceeded. Option C: Incorrect. Operating time doesn't determine responsibility. The 20% contribution rule applies, not operating time. Option D: Incorrect. Not all transmitters are responsible - only those contributing 20% or more of their MPE limit in areas where total limits are exceeded.
知识点
Multiple transmitters, RF exposure, MPE limits, 20 percent rule
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.