If hearing protectors are unused for only a short time, their attenuation according to international standards is reduced drastically Whether this actually occurs was to be investigated in a second study during which also 10 test subjects (Ss) were exposed to noise at a level of 94 dB(A), continuously, for 1 h. In a further test series (TS), during which earplugs instead of ear muffs in the study of chapter 15 with an attenuation of 30 dB were provided, the Ss were exposed to noise at a level of 106 dB(A) for 1 h. The protectors were inserted just 3¾ min after the noise exposure began. According to the equal energy concept and the 3-dB exchange rate, this constellation leads to an equivalent noise exposure of 94 dB(A) / 1 h. Therefore, the attenuation of the earplugs which went unused for 3¾ min during 1 h seems to deteriorate by 18 dB to only 12 dB. Furthermore, the influence of several short-time removals of the earplugs on the attenuation was simulated. The actual effects of the shortened wearing time on the protection of the earplugs were evaluated via audiometric measurements. According to the results, the only slight physiological responses to short periods of earplug removal cannot be interpreted as representing drastic reductions of the attenuation which were predicted in the standards.