The shape of the yin and yang sections of the symbol, actually gives you a sense of the continual movement of these two energies, yin to yang and yang to yin, causing everything to happen: just as things expand and contract, and temperature changes from hot to cold.
Sound is measured in units called decibels. Sounds of less than 75 decibels, even after long exposure, are unlikely to cause hearing loss. However, long or repeated exposure to sounds at or above 85 decibels can cause hearing loss. The louder the sound, the shorter the amount of time it takes for NIHL to happen.
Sudden hearing loss, the rapid loss of 30 decibels or more of hearing ability, can happen over several hours or up to 3 days. (A normal conversation is 60 decibels.) Sudden hearing loss usually affects only one ear. Although there are up to 3 new cases per every 10,000 people each year, doctors are not able to discover the cause in most cases. Illnesses such as heart disease, high blood pressure, and diabetes put ears at risk by interfering with the ears' blood supply.