----------  *SPECTRUM*  ----------

               Electromagnetic Spectrum

                                  Minimum    Maximum        Typical
                                 Cycles/Sec Cycles/Sec    Wavelength

ELF (Ext. Low Freq., Power Lines)   10**0     10**3       3000 miles
VLF (Very Low Freq., AM Radio)      10**3     10**7       1000 feet
VHF (Very High Freq., TV)           10**8     10**9       10 feet
Microwaves (Radar, Microwaves)      10**9     10**11      1 inch
Infrared                            10**12    10**14      10**-3 inch
Visible Light                       10**15    10**15      10**-5 inch
Ultraviolet (ionizing)              10**15    10**17      10**-6 inch
X-Rays (ionizing)                   10**16    10**21      10**-10 inch
Gamma Rays (ionizing)               10**19    10**22      10**-11 inch

   Source: Derived from Washington Post, Dec. 16, 1987, page D3
