<< <  Page 2 of 3  > >>

Mar 18, 2016
Category: General
Posted by: admin

AusNDT Pte Ltd

Oct 15, 2015
Category: General
Posted by: admin

Wijaya Karya

Nov 10, 2013
Category: General
Posted by: admin



Microwave and Radio Frequency Radiation Surveillance

Radio frequency, i.e., microwave and radio wave radiation, is a specific component of the electromagnetic spectrum. Radio frequency radiation is in the non-ionizing portion of the spectrum. Non-ionizing radiation includes the lower frequencies in the electromagnetic spectrum such as ultraviolet and visible light, infrared, microwave and radio wave. 

Electromagnetic radiation consists of vibrating electric and magnetic energy or fields moving through space. For example, electric current in a transmitter circuit establishes electric and magnetic fields in the region around it. As the electric current moves back and forth, the fields continue to build up and collapse, forming electromagnetic radiation. This electromagnetic radiation is characterized in terms of the wavelength and the frequency of vibration.

Microwave and radio wave radiation may be categorized as continuous waves (e.g., communications equipment), intermittent (microwave ovens, medical diathermy equipment, and radio frequency equipment), or pulsed mode (radar systems). Microwave and radio frequency radiation may be transmitted, reflected, or absorbed upon striking an object.

Health Effects

The various types of radiation affect the human body in different ways. For example, ionizing radiation, that contains a tremendous amount of energy and penetrating power, will cause changes in the body's molecular system. On the other hand, as noted, non-ionizing radiation operates at much lower frequencies and is not believed to be as harmful to the human body as ionizing radiation.

It is known, however, that exposure to non-ionizing radio frequency radiation may produce serious biological effects. As high frequency radio frequency radiation, i.e., microwave radiation, penetrates the body, the exposed molecules move about and collide with one another causing friction and, thus, heat. This is known as the thermal effect. If the radiation is powerful enough, the tissue or skin will be heated or burned. Such health effects may or may not be reversible, depending on the particular tissue or organ that is exposed, the intensity of the radiation, the frequency and duration of the exposure, the environmental temperature and humidity, and the body's efficiency in dissipating the heat.

At the present time, there is substantial scientific data that establishes negative health effects associated with microwave radiation. For example, it has been demonstrated that microwave radiation may cause eye and testicular damage. These organs are highly vulnerable to radiation damage because they contain few blood vessels. Therefore, they are unable to circulate blood and dissipate the heat from radiation as effectively as other organs.

An additional health concern involves damage to the eyes. For example, several scientific investigations have shown that cataracts among humans and laboratory animals have occurred as a result of the intense heating of high frequency microwave radiation. Such data has revealed that a particularly important determinant in the causation of microwave radiation-induced cataracts is the time intervals between exposures, i.e., increased time intervals between exposures is thought to allow the body's repair or defense mechanism more opportunity to limit ocular lens damage.

As noted, microwave radiation may also cause damage to the male testes/reproductive organs. Specifically, scientists have demonstrated that exposure to microwave radiation may result in partial or permanent sterility. In addition, some scientific evidence suggests similar effects associated with microwave exposure and female reproductive problems. Furthermore, the scientific literature indicates a relationship between exposure to microwave radiation and birth defects, such as mongolism (Down's Syndrome) and central nervous system damage.

Exposure to radio wave radiation may result in a non-thermal reaction that causes similar molecular interactions as in the thermal effect, but without the heating of the exposed tissue or organ. The site of energy absorption varies with the frequency, that is, exposure to low frequency non-ionizing radio frequency radiation will (theoretically) penetrate the skin and cause molecular interactions similar to those caused by high frequency radio frequency radiation. Complicating such non-thermal reaction, the body's heat and warning system may not provide protection because the energy is absorbed at locations below the nerves.

Another health concern regarding work with radiofrequency equipment is potential electrical shock. This may occur when, under abnormal conditions, the operator is standing in water and comes into contact with a high-frequency generator circuit.

A final concern is associated with the use of cell phones and related equipment. Regarding cell phones, millions upon millions of workers, consumers, and family members (including children) spend a significant amount of time using/talking on their cell phones. Such use of cell phone equipment may result in excessive exposure to radio frequency radiation. If such exposure is significant (based upon the duration or length of time one uses the cell phone, the placement of the cell phone relative to the user's ear, i.e., against or within close proximity to or away from the user's ear, and the amount of radiofrequency radiation emitted by the cell phone), serious health effects may occur. For example, scientific and medical data has demonstrated individuals who use cell phones continuously throughout the (work) day and place the phone directly against their ear have developed related brain tumors. Scientific theory suggests related excessive radiofrequency radiation emissions bombard/penetrate the blood/brain barrier resulting in the growth of brain tumors. As a result of these findings, cell phone users should utilise hands-free equipment rather than holding the cell phone directly against their ear/head.

Microwave and Radio Frequency Radiation Exposure Level Testing

AusNDT™ offers you a service to ensure that the radiation exposure level is acceptable to International/Local Standard and/or Regulation.