IRRSP Exam Study Guide

IRRSP Exam Study Guide An atom, group of atoms, molecules or particles that have acquired or are regarded as having a net electric charge. - Ion Atoms having the same number or protons but a different number on neutrons in the nuclei. Atoms with the same atomic number (the same chemical element) but different atomic weights. - Isotope Any source that disrupts the electrical balance of an atom and results in the production of ions. - Ionization The radation dose or amount of radation that has been absorbed by a substance. Measured in rads (greys). - Absorbed dose The process whereby the particles or photons in a beam of radation are reduced in number or energy as they pass through a medium. - Absorption The activity of a radioisotope is the number of disintegrations that occur for a given quantity of the radioisotope during a given length of time. Activity is measured in curies (becquerel) - Activity The acronym for (As Low As Reasonably Achievable) which means making every effort to maintain and control exposures as far below the dose limits as in practical. This consept comes out of the Code of Federal Regulation 10 CFR Part 20. - ALARA A small electronic device, required to be worn by a radiographer, with an audible alarm set to trigger at 500 mR/h (5000 uSv/h). - Alarming rate meter A positive electrically chargerd particle of radation consisting of 2 protrons and 2 newtrons (same as helium nucleus). It is emitted from the nucleus of many radioactive materials during radioactive decay. ( + charge) - Alpha particle An electrically charged particle of radation emitted from the nucleus of many radioactive materials during radioactive decay. A beta particle is a fast-moving electron, sometimes moving close to the speed of light. ( - charge) - Beta particles High energy, short wavelenghth electromagnetic radation emitted during radioactive decay. - Gamma rays The reduction in the intensity of radation as it passes through a material. - Attenuation A unit if matter consisting of a nucleus (made up of neutrons and protons) and electrons that surround the nucleus. The smallest part of an atom that retains the properties of the element. - Atom The mass/weight of an atom, usually expressed in atomic mass units (AMU). - Atomic mass This unit is based on 1/16 of the weight of an oxygen-16 atom. One neutron or one proton weighs approximately 1 AMU. - Atomic mass units The total number of protons in an atom. The atomic number determines the element and its chemical properties. It is also known as the Z number. - Atomic number The total mass of an atom. It is approximately equal to the total number of protons and neutrons in the nucleus of an atom and measured in atomic mass (AMU). - Atomic weight The SI unit of radiation activity that is equal to one disintegration per second. 3.7*10^10 Bq = 1 Ci. - Becquerel (Bq) The electromagnetic radiation produced by an electrically charged particle, such as an electron, subjected to a change in velocity. It is the German word meaning braking radiation. - Bremsstrahlung