The graph shows the US Department of Labor noise regulation for working without
ID: 1403246 • Letter: T
Question
The graph shows the US Department of Labor noise regulation for working without ear protection. A machinist is in an environment where the ambient sound level is of 85 dB, i.e., corresponding to the 8 Hours/day noise level. The machinist likes to listen to music, and plays a Boom Box at an average level of 82.0 dB.
A. Calculate the INCREASE in the sound level from the ambient work environment level (in dB)
B. A student at a rock concert has a seat close to the speaker system, where the average sound intensity corresponds to a sound level of 118 dB. By what factor does that sound intensity exceed the 2- Hours/day intensity limits from the graph?
Explanation / Answer
part a )
Boom Box at an average level of 82.0 dB
82 = 10^(8.2)
85 = 10^(8.5)
The sound level due to ambient work environment and music is
10log(10^(8.5) + 10^(8.2)) = 86.76 dB
part b )
The sound intensity for 2- Hours/day from the graph = 95dB
95 dB = 0.003162 W/m^2
118 dB = 0.630957 W/m^2
ratio = 199
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.