Limits of Human Exposure to Radiofrequency Electromagnetic Fields in the Frequency Range from 3 KHZ to 300 GHZ - Safety Code 6

Appendix IV Limits of Exposure to Pulsed RF Fields 1.

1. While the average power density of pulsed waves shall be within the limits specified in Tables 1 and 5, the peak value of the instantaneous electric field strength (temporal peak) of the wave shall not exceed 100 kV/m (Sections 2.1.4 and 2.2.4). Calculation of the average power density is discussed in Appendix III.B.
2. For exposures to pulsed RF fields of pulse durations less than 100 milliseconds (ms) and frequencies in the range of 0.1 MHz to 300 000 MHz, the exposure limit in terms of peak power density for a single pulse is based on limiting the energy density of a single pulse according to:
   
   
   1. Energy density of a single pulse must be no greater than one-fifth of the maximum allowable energy density in a 0.1 h time period. In mathematical terms, this is given by⁽⁵⁾

where

• W_P = peak power density exposure limit for a single pulse, in W/m²
• W_L = continuous wave exposure limit as specified in Table 1 or 5, in W/m²
• T = pulse duration as defined in Appendix III.B, in seconds
• T_a = averaging time as specified in Table 1 or 5, in seconds. A maximum of five such pulses is permitted during any period equal to the averaging time.
  
  
  2. If there are more than 5 pulses during any period equal to the averaging time, or if the pulse durations are greater than 100 ms, normal time averaging applies, except that the energy density delivered during any 100 ms period is limited by the formula