A Discussion on Associating THz Safety with 5G Safety

A project on the development of midinfrared free‐electron laser and terahertz (THz) radiation produced by a home‐constructed electron accelerator has recently been launched in the laboratory. A study of THz technology and its applications for biology is one of the emphases and thus THz safety is in focus. This is not only due to the THz radiation itself, but also its association with 5G safety, which has recently become a topic of public concern worldwide. If THz radiation is demonstrated safe, 5G, with the same power, should be safe due to its lower photon energy. The safety issues of both radiations are discussed with different opinions. Herein, safety from physics is discussed and it is pointed out that radiation safety not only depends on photon energy but also radiation power, or the photon dose rate. Through quantitative discussion of the currently used 5G transmission station power, this study confirms that 5G is safe, while THz safety is not yet certain. Therefore, measurement of THz power, a test of THz radiation effect on DNA change, an investigation of the DNA vibration using the THz time‐domain spectroscopy, and molecular dynamics simulation of THz radiation of DNA are suggested.