The human body has five sensory organs, which are the external sensory organs that transform the
physical stimulus generated outside the human body into electrical signals that can activate nerve cells. Can
be heard only through the ear but can be heard through the non-skin.The sound can be useful when listening, but there are noises, the noise is caused by environmental stress The frequency of brain waves
originating from the human brain is basically a frequency of 0 to 30 Hz and exhibits an amplitude of
about 20 to 200㎶. The delta(δ), theta(θ), alpha(α), beta(β), and gamma(γ) are arbitrary classes of
frequencies for EEGs. In normal brain waves, the proportion of allophases is higher than that of the beta
waves, indicating the state of relaxing, while the number of the beta waves expressing the annoyance more
rapidly increases when the noise is heard. , It can be seen that when the noise is reduced to a noise level,
the bass wave in a situation with a lot of stress increases almost immediately, and the exposure in a short
time also takes time to recover from the bass wave. And Neuro Harmony M, a brain wave measuring
device, was used to measure the brain waves of the examinees. As a result of the experiment, it was
found that all the subjects were silent, and the delta waves were higher in the noise environment of the
underground iron when they were silent.In the case of the seta, the silence was higher than the noisy
environment. Beta and Low-Beta, it was found that there was a difference depending on the degree of
noise felt by the experimenters.