emissions of the phone. FCC measures the Specific Absorption Rate (SAR) of the phone, following a very rigorous testing protocol. As is true for nearly any scientific measurement, there is a possibility that the test measurement may be less than or greater than the actual RF emitted by the phone. This difference between the RF test measurement and actual RF emission is because test measurements are limited by instrument accuracy, because test measurement and actual use environments are different, and other variable factors. This inherent variability is known as “measurement uncertainty.” When FCC conducts post-grant testing of a cell phone, FCC takes into account any measurement uncertainty to when determining whether regulatory action is appropriate. This approach ensures that

when FCC takes regulatory action, it will have a sound, defensible scientific basis.

FDA scientific staff reviewed the methodology used by FCC to measure cell phone RF, and agreed it is an acceptable approach, given our current understanding of the risks presented by cellular phone RF emissions. RF emissions from cellular phones have not been shown to present a risk of injury to the user when the measured SAR is less than the safety limits set by FCC (an SAR of 1.6 w/kg). Even in a case where the maximum measurement uncertainty permitted by current measurement standards was added to the maximum permissible SAR, the resulting SAR value would be well below any level known to produce an acute effect. Consequently, FCC's approach with measurement uncertainty will not result in consumers being exposed to any known risk from the RF emitted by cellular telephones.

FDA will continue to monitor studies and literature reports concerning acute effects of cell phone RF, and concerning chronic effects of long-term exposure to cellular telephone RF (that is, the risks from using a cell phone for many years). If new information leads FDA to believe that a change to FCC's measurement policy may be appropriate, FDA will contact FCC and both agencies will work together to develop a mutually-acceptable approach.

Static Electricity, ESD, and Your Palm® Device

Electrostatic discharge (ESD) can cause damage to electronic devices if discharged into the device, so you should take steps to avoid such an occurrence.

Description of ESD Static electricity is an electrical charge caused by the buildup of excess electrons on the surface of a material. To most people, static electricity and ESD are nothing more than annoyances. For example, after walking over a carpet while scuffing your feet, building up electrons on your body, you may get a shock—the discharge event—when you touch a metal doorknob. This little shock discharges the built-up static electricity.

ESD-susceptible equipment Even a small amount of ESD can harm circuitry, so when working with electronic devices, take measures to help protect your electronic devices, including your Palm® device, from ESD harm. While Palm has built protections against ESD into its products, ESD unfortunately exists and, unless neutralized, could build up to levels that could harm your equipment. Any electronic device that contains an external entry point for plugging in anything from cables to docking stations is susceptible to entry of ESD. Devices that you carry with you, such as your Palm device, build up ESD in a unique way because the static electricity that may have built up on your body is automatically passed to the device. Then, when the device is connected to another device such as a docking station, a discharge event can occur.

Precautions against ESD Make sure to discharge any built-up static electricity from yourself and your electronic devices before touching an electronic device or connecting one device to another. The recommendation from Palm is that you take this precaution before connecting your Palm device to your computer, placing a device in a cradle, or connecting it to any other device. You can do this in many ways, including the following:

Ground yourself when you’re holding your device by simultaneously touching a metal surface that is at earth ground. For example, if your computer has a metal case and is plugged into a standard three-prong grounded outlet, touching the case should discharge the ESD on your body.

Increase the relative humidity of your environment.

Install ESD-specific prevention items, such as grounding mats.

Conditions that enhance ESD occurrences Conditions that can contribute to the buildup of static electricity in the environment include the following:

Low relative humidity.

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Palm 680 manual Static Electricity, ESD, and Your Palm Device