Cell Phone Safety: What the FCC Didn't Test

Skeptics of the safety of cellular phones have seized upon product warnings as evidence that the ubiquitous devices may be exposing Americans to far more radiation than regulators measure.

The warnings stem from an odd quirk in federal testing procedures designed to ensure the safety of cellular phones. In 2001, the Federal Communications Commission released a set of guidelines for manufacturers that required all cell phones sold in the U.S. to emit a specific absorption rate (SAR) of not more than 1.6 watts of radio-frequency energy per kilogram of body tissue, a standard deemed safe given the state of scientific knowledge about thermal harm from radio-frequency waves. The standard was considered a so-called worst-case scenario, accounting for the energy emitted when the phone was transmitting at full power all of its various signals — such as Bluetooth, Wi-Fi and cellular. But the FCC testing regulations notably chose not to simulate a situation in which the phone was broadcasting at full power while inside a shirt or pants pocket flush against the body, an odd oversight given the known habits of many cellular-phone users. As a matter of physics, radio-frequency energy generally increases sharply as distance is reduced.