At the power levels most machines operate, probably not. However, the FCC in the US has set limits as to how much RF exposure the general public and workers in the communication industry are allowed. OSAH in the US also put their two cents in, making the occupational exposure limit the same as the lower general public limit.
Fortunately, for those concerned about being legal exposure wise, there is the six minute averaging loophole. You can be exposed to a radio frequency field at 200% of the limit for three minutes, as long as you have no exposure at all for the next three minutes.
The exposure limits were determined by the one universally agreed to effect of radio frequency energy on the human body which is heating.
The original Rife equipment is estimated to have an output power of 50 watts. The subjects treated by Rife were probably right at todays exposure limit if they were being treated for three minutes at the distance from the machine described.