CLC number: Q6
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Received: 2006-02-08
Revision Accepted: 2006-10-08
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Lindenblatt G., Silny J.. Evaluation and comparison of 50 Hz current threshold of electrocutaneous sensations using different methods[J]. Journal of Zhejiang University Science B, 2006, 7(12): 933-946.
@article{title="Evaluation and comparison of 50 Hz current threshold of electrocutaneous sensations using different methods",
author="Lindenblatt G., Silny J.",
journal="Journal of Zhejiang University Science B",
volume="7",
number="12",
pages="933-946",
year="2006",
publisher="Zhejiang University Press & Springer",
doi="10.1631/jzus.2006.B0933"
}
%0 Journal Article
%T Evaluation and comparison of 50 Hz current threshold of electrocutaneous sensations using different methods
%A Lindenblatt G.
%A Silny J.
%J Journal of Zhejiang University SCIENCE B
%V 7
%N 12
%P 933-946
%@ 1673-1581
%D 2006
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.2006.B0933
TY - JOUR
T1 - Evaluation and comparison of 50 Hz current threshold of electrocutaneous sensations using different methods
A1 - Lindenblatt G.
A1 - Silny J.
J0 - Journal of Zhejiang University Science B
VL - 7
IS - 12
SP - 933
EP - 946
%@ 1673-1581
Y1 - 2006
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.2006.B0933
Abstract: 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 μA (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 1 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. Therefore, 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 modern 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.
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