Protection Against Cell Phone RadiationCell Phone Radiation ProtectionThe derivation of these standards goes back to the 1970s. The first ELVs for microwaves were issued in 1979 by the Chinese Ministry of 4th Machine Industry (CM4MI) as "temporary sanitary rules for workplace"., but these were extended and amended in 1989 by CMPH. CM4MI had carried out during 1975-77 a large cross sectional epidemiological study with a working group including Zhejiang Medical University, Beijing Jiuxian Qiao Hospital and another 15 epidemic preventive stations in factories and institutions.In this large study four groups were formed, 0,