Electromagnetic radiation, one of the various types of energies to which people can be sensitive, is by far the most easily found.
Firstly, you should understand that the phrase really applies to anything which is associated with electrical or magnetic fields. Apart from natural light itself, which originated from the sun, a modern home has many such sources.
If you have a microwave or a cell-phone you have sources of electromagnetic radiation (emr). If you have light bulbs or fluorescent lights, you also have emr sources.
In other words, every home has emr to one extent or another.
Ordinary light does not, by and large, affect people, but other types certainly can. Usually, the field of influence which is put out by the source is what is measured. So the extent to which the radiation can be felt is what determines the electromagnetic field (or emf).
Now it is quite easy to purchase a hand-held gadget which will show you where it finds such field coming from an appliance.
However, the point to remember is that, although emf radiation can be measured by a machine, it is not the machine which is being affected by it. So, bear in mind that humans can be VERY sensitive indeed to such things.
How sensitive?Well, it has been shown that very weak electromagnetic fields indeed such as are commonly found near appliances in homes can affect some peoples’ heart rates, breathing, skin sensitivity and other factors.
Such radiation does not directly cause illnesses such as cancer, but they do prevent the body from automatically repairing itself. So, continual exposure to even fields as low as 200 nanoTesla (a VERY low number) will have a negative effect on your body.
Therefore, although meters can be bought which will show the strength of an emf, it is not always useful for sensitive people who already know of its existence!
Incidentally, another use of emf meters is in the field of ghost-hunting. It is thought by many ghosthunters that ghosts and suchlike apparitions emit an electro-magnetic field which can, therefore be detected.
The fact that some people can feel the effects of such radiation has led to the development of various types of emf protection.
The fact that electromagnetic radiation has several natural sources has led many people to ignore this aspect. For example the following are all on the emf spectrum:
- radio waves
- infrared waves
- visible light
- ultraviolet light
- gamma rays