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Cell phones are everywhere with almost every function imaginable. Some, goes the joke, even can make phone calls.

A lot goes into the phone and, before it goes to market it has to go through multiple simulations for effectiveness and safety. One of the most important tests is for radiofrequency energy. RF is a rate of oscillation within the range of about 3 Hz to 300 GHz. This range corresponds to frequency of alternating current electrical signals used to produce and detect radio waves. There are international standards in existence that must be reached.

In the United States, the Federal Communications Commission (FCC) has guidelines that were derived from the recommendations of the National Council on Radiation Protection and Measurement (NCRP) and the Institute of Electrical and Electronics Engineers (IEEE). Many European countries use similar guidelines developed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP), which in turn are similar to those of NCRP and IEEE.

The NCRP, IEEE and ICNIRP have identified a whole-body Specific Absorption Rate (SAR) value of four watts per kilogram as a threshold of exposure at which harmful biological effects may occur. The FCC limit for exposure to RF energy absorbed in the head of a cell-phone user is a SAR level of 1.6 W/kg.

Simulation is the most efficient way to test for SAR. "To set the stage, for 10-15 years, software companies were solving the handset manufacturers' problems," says Ryan Schneider, Co-founder and Chief Technology Officer of Acceleware in Calgary, Alberta, Canada. "The software package was CAD and imported into the electromagnetic simulation tool and run. The end-user sees a picture of the phone.