Leakage currents, tiny currents flowing from an everyday-life appliance through the body to the ground, can cause a non-adequate perception （called electrocutaneous sensation, ECS） or even pain and should be avoided...Leakage currents, tiny currents flowing from an everyday-life appliance through the body to the ground, can cause a non-adequate perception （called electrocutaneous sensation, ECS） or even pain and should be avoided. Safety standards for low-frequency range are based on experimental results of current thresholds of electrocutaneous sensations, which however show a wide range between about 50 pA （rms） and 1000 μA （rms）. In order to be able to explain these differences, the perception threshold was measured repeatedly in experiments with test persons under identical experimental setup, but by means of different methods （measuring strategies）, namely： direct adjustment, classical threshold as amperage of 50% perception probability, and confidence rating procedure of signal detection theory. The current is injected using a I cm2 electrode at the highly touch sensitive part of the index fingertip. These investigations show for the first time that the threshold of electrocutaneous sensations is influenced both by adaptation to the non-adequate stimulus and individual, emotional factors. Theretbre, classical methods, on which the majority of the safety investigations are based, cannot be used to determine a leakage current threshold. The confidence rating procedure of the modem signal detection theory yields a value of 179.5 μA （rms） at 50 Hz power supply net frequency as the lower end of the 95% confidence range considering the variance in the investigated group. This value is expected to be free of adaptation influences, and is distinctly lower than the European limits and supports the stricter regulations of Canada and USA.展开更多
The present paper is aimed to better illustrate the possible association between a particular extremely weak field, the air ions, and the human health response to this solicitation. Methods and instruments for this ki...The present paper is aimed to better illustrate the possible association between a particular extremely weak field, the air ions, and the human health response to this solicitation. Methods and instruments for this kind of analysis are here given in the form of a project： a ＂Ions meter＂, to reveal and characterize the properties of the air ions, and ＂APEC 300＂, an advanced electronic device, both instruments are with a HPR （high power of resolution）. APEC 300 can give the response to the possible health effects by measurements of two electrocuteaneous parameter： the potential level and the impedance. The power of resolution of APEC 300 is much higher than that of other usual devices, for instance, the EAV ones （electroacupuncture）, this instrument will be completely ready within few weeks.展开更多
文摘Leakage currents, tiny currents flowing from an everyday-life appliance through the body to the ground, can cause a non-adequate perception （called electrocutaneous sensation, ECS） or even pain and should be avoided. Safety standards for low-frequency range are based on experimental results of current thresholds of electrocutaneous sensations, which however show a wide range between about 50 pA （rms） and 1000 μA （rms）. In order to be able to explain these differences, the perception threshold was measured repeatedly in experiments with test persons under identical experimental setup, but by means of different methods （measuring strategies）, namely： direct adjustment, classical threshold as amperage of 50% perception probability, and confidence rating procedure of signal detection theory. The current is injected using a I cm2 electrode at the highly touch sensitive part of the index fingertip. These investigations show for the first time that the threshold of electrocutaneous sensations is influenced both by adaptation to the non-adequate stimulus and individual, emotional factors. Theretbre, classical methods, on which the majority of the safety investigations are based, cannot be used to determine a leakage current threshold. The confidence rating procedure of the modem signal detection theory yields a value of 179.5 μA （rms） at 50 Hz power supply net frequency as the lower end of the 95% confidence range considering the variance in the investigated group. This value is expected to be free of adaptation influences, and is distinctly lower than the European limits and supports the stricter regulations of Canada and USA.
文摘The present paper is aimed to better illustrate the possible association between a particular extremely weak field, the air ions, and the human health response to this solicitation. Methods and instruments for this kind of analysis are here given in the form of a project： a ＂Ions meter＂, to reveal and characterize the properties of the air ions, and ＂APEC 300＂, an advanced electronic device, both instruments are with a HPR （high power of resolution）. APEC 300 can give the response to the possible health effects by measurements of two electrocuteaneous parameter： the potential level and the impedance. The power of resolution of APEC 300 is much higher than that of other usual devices, for instance, the EAV ones （electroacupuncture）, this instrument will be completely ready within few weeks.
