In the main figure for HEGduino, it says that the low power of the sensor circuit protects tissue. While it is intuitive that an extremely high power EM field in close proximity would cause damage, I was wondering what backing there is for this statement specifically in relation to the device. Doing some searching on the subject, I found some relevant research, but it's a bit difficult for me to parse so I figured I'd ask and see if there was an easy answer.
Part of my concern comes from the fact I've been getting headaches after/during long (1-3hr) sessions using the device purely for recording, without attempting to control blood flow. Pain usually starts nearing the end of the first hour and continues for about 30-45mins after discontinuing use. It is possible that the discomfort comes from having the device strapped there and the hardness of the sensors/emitters, and I'll do a trial tomorrow to test that, but I find it unlikely.