NEU Abbreviated
Study Guide

•  2.54 cm = 1 inch. 30.4 cm = 1 foot.

•  2.83E4 cc = 1cubic foot. 

•  The atom is the smallest part of an element that can be
      separated by chemical reaction.

•  Atomic number is the number of protons. This is known as the
      Z number.

•  Atomic mass number is the sum of the number of protons
     and neutrons in the nucleus. This is known as the A number.
     Protons and Neutrons are called Nucleons.

•  One atomic mass unit (AMU) is equal to 1/12 the mass of a
      carbon-12 nucleus. (1.6604E-24 g.) (Also called a Dalton after Chemist
     John Dalton, sometimes abbreviated Da.)

•  Radioactivity is the process by which the nucleus of unstable
      nuclides disintegrates with the resulting emission of nuclear
      radiation. Becquerel discovered radiation.

•  Half-Life is the term in which half of the atoms of a particular
      radioactive substance decay to another nuclear form, or element.

•  Ionization is the general process of producing Ions by the
      passage of high energy particles.

•  Chronic radiation exposures are those involving continuous
      or repeated exposures over a relatively long time interval.

•  Acute radiation exposures are involving relatively large doses
      in a short time.

•  Somatic effects refer to the individual that received the exposure.

•  Isotopic abundance is the amount of the isotope (percentage)
      present in a normal natural mixture of the element.

•  Isotopes are defined as atoms with the same atomic number
      (Z) but different atomic mass number (A).

•  Linear Attenuation Coefficient: " A fraction decrease in energy
      through absorption of material inverse of the mean free path".
      This is the name that describes the number of interactions
      per unit length.

•  The unit for energy in nuclear reactions is the electron volt (ev),
      which is the amount of energy gained by an electron when
      accelerated through a potential difference of one volt.1 Mev
      is 1E6 ev.

•  A Curie is 3.7E10 dps (one dps is equal to one Becquerel) or
      2.22E12 dpm. A Pico Curie is 2.22 dpm

•  The Roentgen is a measure of Exposure of air to gamma and
      x-rays. The energy absorbed by one gram of air exposed to
      one Roentgen of gamma rays is 87 ergs. There is no SI
      equivalent.

•  The RAD is used as a unit of measurement for the energy
      deposited by any radiation in any material. 1 Rad = 100 ergs/gm
      any radiation in any material.  100 Rad = 1 Gray.

•  REM is Dose Equivalent resulting from any type of radiation
      exposure. Rem is the unit of measure for internal exposure.
      REM Dose = RAD Dose x Quality Factor. 100 Rem = 1 Sievert.

•  Quality Factor is used to convert Absorbed Dose (RAD) to
      Biological Effect (REM). QF: Gamma = 1, Beta = 1, Thermal
      Neutron = 2 (NEU) to 3 (DOE), Fast Neutron = 10, Alpha = 20,
      Proton = 10.

•  The new 10 CFR 20 and 10 CFR 835 is based on ICRP #26.

•  A major change in dose limits between the old and revised
     10 CFR 20 is that the old limits are based on calendar quarter
     time period and the revised limits are based on an annual
     time period.

•  An individual must be supplied with a personnel monitoring
     device if entering the restricted area and will receive or is
     likely to receive an exposure in excess of 10% of the (federal)
     limit. A minor will be allowed 10% of an adults limit per year.

•  When entering a high radiation area, you need personnel
      monitoring devices.

•  TODE, Dose limit for the extremities as per 10 CFR 20 is 50
      Rem/yr.

•  DDE, deep dose equivalent, is dose to the whole body (WB)
      from 'external' radiation exposure. 

•  TEDE, total effective dose equivalent, is the sum of all internal
      and external dose.

•  CDE is the dose equivalent from Internal exposure to an
      individual organ or tissue, as calculated over a 50 year period
      after the exposure. CEDE equates risk from organ to risk from
      whole body dose.

•  WF, weighting factor, is the equivalent whole body exposure
      from exposure of all organs due to radioactive material intake.

•  According to the ICRP "ALI" stands for Annual Limit on Intake.
      1 ALI = 2000 DAC Hrs = 5 Rem.

•  The annual PSE limit for TEDE is 5 Rem. PSE = Planed special
      exposure. The NRC must be notified prior to any PSE.

•  A radiation area is posted at 5 mr/hr @ 30 cm.

•  The revised 10 CFR 20 specifies that radiation levels be
      measured at 30 cm.

•  Black lettering is now ok for Radiation signs.