The EMF-823 is designed to provide user a quick, reliable and easy way to measure electromagnetic field radiation levels around power lines, home appliances, computers, monitors, transformers, and industrial devices. The EMF-823 EMF meter is a cost effective, hand-held instrument designed and calibrated to measure electromagnetic field radiation at different bandwidths down to 50 Hz/60 Hz. Often used in paranormal investigations as well.
It is recommended to measure for the presence of EMFs inside and outside of your home and business regularly. As "hot spots" are detected by the EMF tester, re-arrangement of the living and working areas is lightly recommended. Always try your best to avoid long term exposure to strong electromagnetic fields.
Link to the technical data sheet that is provided for Lutron EMF-823
This EMF tester is specifically designed to determine the magnitude of electromagnetic field radiation generated by power lines, computer's monitor, TV sets, video machinery and many other similar devices.
CAUTION: ELECTROMAGNETIC FIELD EXPOSURE Claims by some scientists that long term exposure to electromagnetic field may be the cause of childhood leukemia & other forms of cancer. Complete answers to any of these and related questions are not currently available. At the present time the most common practice is to avoid excess exposure over long period of time. "Prudent Avoidance" as stated by the Environmental Protection Agency(EPA) USA is recommended.