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Resistivity of the human body or tissue

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kender

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resisitivity human body frequence

Colleagues,

I’m trying to estimate the skin depth of the human body at 13.5MHz (one of the RFID frequencies). To do this I need to know the resistivity of the body or the tissue. I couldn’t find this number on the web. Does anyone know this number? The closest thing I could was resistivity of the seawater, which is 0.2 Ohm-meters. Is the resistivity of the human tissue much different from that of the seawater? Is it frequency-dependednt?

Cheers,
Nick
 

ShuklaS

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human body conductivity

Hi,
I Dont have the exact value but the body conductivity vary with blod circulation
regards
 

kender

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different tissues in the human body +salinity

I just realized that the medical saline has 0.9% salt and seawater has 3.5% salt. That could make a big difference in conductivity. The temperature difference between the normal conditions (25C) and the body temperature (37C) can make a big difference in conductivity too. Does anyone know of a table or a formula or a program that allows to find the conductivity of a salt solution of a given concentration at a given temperature?

Cheers,
Nick
 

kender

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ricy

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Hi Kender

of course: the dielectric properties of human tissue are depending on the frequency!
Take a look here: https://www.fcc.gov/fcc-bin/dielec.sh
You can type in your frequency (13.5 MHz?) and get the values for different types of human tissue; e.g. skin dry: sigma=0.237/eps=286.3

hope this helps :)
best: Ricy
 
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JAMSUL

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But how to calculate the total complex value of the skin for example, Epslon and sigma how to add them to get the total dielectric value or the real value i mean.

Regards


Hi Kender

of course: the dielectric properties of human tissue are depending on the frequency!
Take a look here: OET -- Radio Frequency Safety
You can type in your frequency (13.5 MHz?) and get the values for different types of human tissue; e.g. skin dry: sigma=0.237/eps=286.3

hope this helps :)
best: Ricy
 

js

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what are dielectric properties at low frequencys?
 

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