Tinnitus masker issues associated with use of tinnitus maskers: the "safe" level of continuous sound depends on the duration of the sound. For maskers worn continuously, or most of the day, a safe level is no more than 70db, in accordance with EPA maximum safe exposure level for 24-hour environmental sound. Maskers louder than 45db or so (the ambient background level of an average home living area) may start to interfere with understanding conversation (about 60db). Masking of high frequency tinnitus (>6,000hz) is difficult because of the resonance characteristics of the human ear as well as high frequency limitations of in-ear devices.
Body odour and sexual attraction Body odour and sexual attraction Odour is sensory stimulation of the olfactory membrane of the nose by a group of molecules. Certain body odours are connected to human sexual attraction. Humans can make use of body odour subconsciously to identify whether a potential mate will pass on favourable traits to their offspring. Body odour may provide significant cues about the genetic quality, health and reproductive success of a potential mate. Body odour affects sexual attraction in a number of ways including through human biology, the menstrual cycle and fluctuating asymmetry. It also affects the sexual attraction of insects and mammals.