A case study on hospital noise reduction with flexible curtain track is available on the Medical Construction & Design website.
According to the study, Florence Nightingale is credited with bringing up the issue of noise in 1859, saying "Unnecessary noise, or noise that creates an expectation in the mind, is that which hurts a patient." And, [it is] "... the most cruel absence of care, which can be inflicted either on the sick or well."
The environment of the 21st century hospital is substantially louder, more complex and more difficult to control than that of Nightingale's time. An article in the Boston Globe on noise in hospitals reported that noise levels have doubled since the 1960s.
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