home phone frequency danger?

[Hoosier Daddy]

home phones use 2.4GHz... microwaves are .3GHz... why are they legal?

[Numbat]

There are studies.

Incidence data from the Surveillance, Epidemiology and End Results (SEER) program of the National Cancer Institute have shown no increase between 1987 and 2005 in the age-adjusted incidence of brain or other nervous system cancers despite the dramatic increase in use of cellular telephones

Although this quote is about cellphones, it should be obvious that if there was an increased incidence of cancers it would show up over the timescale of cellphone use since that is also the range of home cordless phone use (brought about by the introduction of integrated circuits - without which none of these devices would be possible). If the incidence was not at the same rate as that of the ramp up of cell phone use (and cordless phones) then it will not have been caused by them.