MEASUREMENT OF THE LEVEL OF RADIATION EMISSION FROM COMMON ELECTRIC LIGHT SOURCES
CHAPTER ONE:
BACKGROUND OF STUDY
INTRODUCTION
Energy emitted from a source is generally referred to as radiation. Examples include heat or light from the sun, microwaves from an oven, X-rays from an x-ray tube and gamma rays from radioactive elements. Here we are concerned with only one type of radiation “ionizing radiation” which occurs in two forms – waves or particles.
Ionizing radiation consists of particles and photons that have sufficient energy to ionize atoms in the human body, thus inducing chemical changes that may be biologically important for the functioning of cells.
The greatest exposure to ionizing radiation is from natural sources. Humans have always been exposed to ionizing radiation, since natural sources existed on earth even before life emerged. Until the end of the 19th century human beings were exposed only to natural radiation. The discovery of X-rays by Wilhelm Rontgen in 1895 and of radioactivity by Henri Becquerel in 1896 led to the development of many applications of ionizing radiation and to the introduction of man-made radiation.
Light is defined as the electromagnetic radiation with wavelength between 380 and 750nm and which is visible to the human eye which is visible to the human eye. Electromagnetic radiation such as light, is generated by changes in movement (vibration) of electrically charged particles, such as parts of heated molecules or electrons in atoms (both processes play a role in the glowing filament of incandescent lamps whereas the latter occurs in fluorescent lamps.
A light bulb is a device that produces light from electricity. In addition to lightning or dark space, they can be used to show an electronic device on, to direct traffic, for heat and many other purposes.
MEASUREMENT OF THE LEVEL OF RADIATION EMISSION FROM COMMON ELECTRIC LIGHT SOURCES
