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The continuous growth of wireless communication has in the recent past raised public

awareness and concerns about the potential health hazards due to exposure

to “waves” (electromagnetic ﬁ elds). Two non-proﬁ t international bodies have been asked

to address this concern: the ICNIRP (International Commission on Non-Ionizing Radiation

Protection) and the WHO (World Health Organization).

In particular since 1992 WHO has been studying the potential risks associated with so called

non-ionizing radiations and in 1998 the ICNIRP has published guidelines that each country

should transpose into local laws and regulations. These guidelines are based on the effects

that these radiations have on body temperature. Detailed information are available

on WHO (www.who.int) and ICNIRP (www.icnirp.org) web sites.

What are reference levels?

To protect people from potential hazards, limits have

been ﬁ xed by international organizations. These limits are

called Reference Levels and are the maximum allowed

E-ﬁ eld for a given frequency. These levels are derived from

limits on the maximum allowable body tissue temperature

increase caused by the ﬁ elds. The restrictions refer to the

SAR values (Speciﬁ c Absorption Rate) that quantify the

rate at which RF (radio frequency) energy is absorbed by

the body. SAR values correspond to a temperature in-

crease in a localized area of tissues in the human body.

SAR values are challenging to measure in real environ-

ments, which is why equivalent E-ﬁ eld reference levels

have been calculated.

Why do we measure exposure levels?

Whenever there is electricity (voltage or current)

an electromagnetic ﬁ eld (EMF) arises. All types

of wireless transmissions (radio/TV broadcasting,

voice/data wireless communication) use

electromagnetic ﬁ elds. The generated ﬁ eld

propagates in waves and is all around us even if we

cannot see it or hear it. The electromagnetic ﬁ eld has

two components: the Electric (E) Field and Magnetic

(H) Field, and they are proportional with each other.

ICNIRP - Reference levels for exposure to electric ﬁ elds

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