"To maintain compliance with FCC, IC, MIC, and EU RF exposure guidelines when you carry the BlackBerry device on your body, use only accessories equipped with an integrated belt clip that are supplied or approved by Research In Motion (RIM). Use of accessories that are not expressly approved by RIM might violate FCC, IC, and EU RF exposure guidelines and might void any warranty applicable to the BlackBerry device. If you do not use a bodyworn accessory equipped with an integrated belt clip supplied or approved by RIM when you carry the BlackBerry device, keep the BlackBerry device at least 0.98 in. (25 mm) from your body when the BlackBerry device is transmitting..."
"To reduce radio frequency (RF) exposure consider these safety guidelines: . . . Use hands-free operation if it is available and keep the BlackBerry device at least 0.98 in. (25 mm) from your body (including the abdomen of pregnant women and the lower abdomen of teenagers) when the BlackBerry device is turned on and connected to the wireless network."
Time, Swampland Blog - BlackBerry: Keep Our Phones Away From Your Body
Picture Credit: Mobile Phones Reviews - Blackberry 9000 Bold Review