EMF radiation is actually generated by electromagnet , any device which uses magnetic coils internally creates such radiation. When certain types of radiation transmits then it's harmful for the human body.

A Radiation meter and Radiation detector can be used in such a place to detect that field and inform you about the dangerous radiation around you. Radiation meter and detector will also show you the intensity of magnetic radiation so you can take safety precautions to reduce the magnetic radiation.

EMF Radiation Detector - Magnetic Field Detector also detects electronic devices like Cell phones,laptops, WiFi,network devices etc which emit a form of radio frequency radiation at the lower end of the non-ionizing radiation spectrum.

Ionizing Radiation : This high-level radiation which has the potential for cellular and DNA damage.
1- Non-Ionizing Radiation:
✔ Extremely Low Frequency (ELF)
✔ Radio Frequency (RF)
✔ Microwaves
✔ Visual Light

2- Ionizing Radiation:
✔ Ultraviolet (UV)
✔ X-Rays
✔ Gamma

Electromagnetic fields are energy areas which are created by electronic devices. There are two parts in the field. (1 electric 2- magnetic).
Electric field is created by differences in voltage and the magnetic fields are created when there,s electric current running to a device.