First of all, to quote an engineer on pg. 114 of Rigmor Granlund-Lind's online PDF book "Black On White":
"I am a safety engineer and have conducted many measurements at many different places. We acquired a Holaday EM field meter...my electro-hypersensitivity came during one week in connection with dental treatment...to conduct measurements and at the same time be EHS has given me an insight...if someone were to ask me if I wanted to work eight hours at a smelting plant with huge electric furnaces, or two hours at our HQ temp office, I would choose the smelting plant without hesitation...there are 100 times more milliTesla at the smelting plant than at the office..."
The above engineer's comments show that you can't rely on so-called "scientific" instruments. They do not reflect REAL LIFE as is mentioned in more detail in that book.