Nokia N81 - Manual (Page 140)

Additional safety information
140
Your mobile device is also designed to meet the
requirements for exposure to radio waves established by
the Federal Communications Commission (USA) and
Industry Canada. These requirements set a SAR limit of 1.6
W/kg averaged over one gram of tissue. The highest SAR
value reported under this standard during product
certification for use at the ear is 0.93 W/kg and when
properly worn on the body is 0.60 W/kg.