Do Televisions Give Off Radio Signals?

Humans are constantly exposed to background radiation from natural sources like the earth and space. We are also exposed to man-made radiation from electronic products like x-ray machines, televisions, microwave ovens, and radar devices. While some devices intentionally emit radiation for beneficial purposes, like x-rays, others, like televisions, emit radiation unintentionally. This raises the question: do televisions emit harmful radiation, and specifically, do they give off radio signals?

Televisions, specifically older models using cathode ray tubes (CRTs), do emit a small amount of electromagnetic radiation. This includes a very low level of x-rays due to the high voltage used to accelerate electrons within the tube. However, modern televisions utilizing LCD or Plasma display technology do not produce x-rays. While CRT televisions can produce radio frequency (RF) signals as a byproduct of their operation, these are generally very weak and contained within the circuitry of the device. They are not the intended output signal and are different from the intentional radio waves used for broadcasting television signals.

The concern about radiation from televisions historically stemmed from the use of CRTs. The high voltage within these tubes could generate x-rays. To address this, the Radiation Control for Health and Safety Act of 1968 was enacted, leading to the establishment of safety standards for electronic products, including televisions. The FDA set a limit of 0.5 milliroentgens per hour for x-ray emissions from television receivers. This standard ensured that televisions manufactured after January 15, 1970, did not emit harmful levels of x-rays.

The primary way televisions transmit information is through radio waves, specifically in the VHF and UHF bands. These radio waves are broadcast from television stations and received by the television’s antenna. The television then decodes these signals to produce the picture and sound we see and hear. This is a deliberate and controlled emission of radio waves, entirely different from the unintentional and minimal RF leakage from a CRT television’s internal circuitry.

The FDA requires manufacturers to certify that their television products meet the established radiation safety standards. Manufacturers must submit reports detailing their quality control and testing procedures to ensure compliance. The FDA also monitors imported televisions to ensure they adhere to the standards.

Modern flat-panel televisions using LCD or Plasma technology do not emit x-rays and pose no known health risks from radiation. While CRT televisions can produce minimal amounts of x-rays and unintentional RF signals, advancements in technology and stringent safety regulations have effectively mitigated any potential harm. Today’s televisions are safe to use under normal operating conditions.