Course outline Course outline Radiation Safety Officer Radiation Safety Officer � Monday Monday - - Scientific and technical basis Scientific and technical basis � Training Class Training Class � Tuesday Tuesday - - Instruments Instruments � � Wednesday Wednesday – Regulatory stuff Wednesday Wednesday Regulatory stuff Regulatory stuff Regulatory stuff � � Thursday Thursday – – The art of being an RSO The art of being an RSO Andrew Karam, Ph.D., CHP Andrew Karam, Ph.D., CHP � � Friday Friday – – Case studies and wrap Case studies and wrap- -up up paksbi@rit.edu paksbi@rit.edu � Historical perspective Historical perspective � Radiation discovered in 1895 by Roentgen Radiation discovered in 1895 by Roentgen � A historical perspective A historical perspective � Radioactivity discovered by Bequerel in 1896 Radioactivity discovered by Bequerel in 1896 � � Radiation injury recognized by 1900 Radiation injury recognized by 1900 Radiation injury recognized by 1900 Radiation injury recognized by 1900 � � X- -rays and radioactivity (mostly radium) rays and radioactivity (mostly radium) � used for legitimate and quack medical used for legitimate and quack medical procedures for several decades procedures for several decades Historical perspective (cont.) Historical perspective (cont.) What this means…. What this means…. � Manhattan Project gave radiation studies Manhattan Project gave radiation studies � We have over a century of experience We have over a century of experience � impetus impetus working with radiation and radioactivity working with radiation and radioactivity � Atomic weapons testing and reactor Atomic weapons testing and reactor p p g g � We know more about the health effects of � We know more about the health effects of We know more about the health effects of We know more about the health effects of � � accidents have had biggest impact on accidents have had biggest impact on radiation than about virtually any other radiation than about virtually any other public’s current view of radiation and public’s current view of radiation and harmful substance harmful substance radioactivity radioactivity � Anyone who says otherwise is itching for a Anyone who says otherwise is itching for a � Other uses include medical, research, and Other uses include medical, research, and � fight! fight! industrial industrial 1
Medical uses Medical uses How and where we use How and where we use � Cancer therapy Cancer therapy � radiation and radioactivity radiation and radioactivity � X- -ray and CT for diagnostic purposes ray and CT for diagnostic purposes � � X-ray and fluoroscopy in the OR X ray and fluoroscopy in the OR ray and fluoroscopy in the OR ray and fluoroscopy in the OR � � Radiopharmaceuticals for medical Radiopharmaceuticals for medical � diagnosis diagnosis � Radioactive immunoassay (RIA) Radioactive immunoassay (RIA) � measurements to diagnosis disease measurements to diagnosis disease Research uses Research uses Industrial uses Industrial uses � Industrial linear accelerators Industrial linear accelerators � � Radioactively Radioactively- -tagged molecules used as tagged molecules used as � Radiography devices Radiography devices tracers of biological activity tracers of biological activity � � Gauges (tank levels, thickness, etc) Gauges (tank levels, thickness, etc) g g ( ( , , , , ) ) � Gene sequencing � Gene sequencing Gene sequencing Gene sequencing � � Electron and ion beams (welding, ion Electron and ion beams (welding, ion � Irradiation of cells or organisms for Irradiation of cells or organisms for � implantation, etc.) implantation, etc.) research purposes research purposes � Well logging and soil density gauges Well logging and soil density gauges � Toxicological studies (biokinetics of toxins Toxicological studies (biokinetics of toxins � � Smoke detectors, self Smoke detectors, self- -illuminating signs, illuminating signs, and drugs) and drugs) � and other consumer products and other consumer products Nuclear reactors Nuclear reactors � The US generates about 20% of its The US generates about 20% of its electricity with about 100 nuclear power electricity with about 100 nuclear power Background information Background information plants plants � World W W World-wide, nearly 500 nuclear reactors ld ld wide, nearly 500 nuclear reactors id id l l 500 500 l l t t produce about 16% of the world’s produce about 16% of the world’s electrical power electrical power � Nuclear reactors are also used to produce Nuclear reactors are also used to produce isotopes for medical, industrial, research, isotopes for medical, industrial, research, and military uses and military uses 2
Protons and neutrons Protons and neutrons Atomic structure Atomic structure � Protons carry a positive charge, and repel each Protons carry a positive charge, and repel each � Atoms have a nucleus in the center of an Atoms have a nucleus in the center of an other other outer cloud of electrons outer cloud of electrons � To assemble an atom, it is necessary to have a To assemble an atom, it is necessary to have a force to overcome the electrostatic repulsion of force to overcome the electrostatic repulsion of p � The nucleus contains both protons and � The nucleus contains both protons and The nucleus contains both protons and The nucleus contains both protons and the protons the protons neutrons neutrons � Neutrons carry the strong nuclear force, and Neutrons carry the strong nuclear force, and � The number of electrons is generally equal The number of electrons is generally equal they act as the “glue” that holds the protons they act as the “glue” that holds the protons to the number of protons to the number of protons together together � The number of protons is what determines The number of protons is what determines � There is an optimal neutron:proton ratio to There is an optimal neutron:proton ratio to the chemical properties of an atom the chemical properties of an atom make an atom stable make an atom stable half-life versus decay energy, alpha emitters In general… In general… 1E+12 1E+10 half-life (yrs) 1E+08 1E+06 � Atoms want to have the right ratio of Atoms want to have the right ratio of 10000 100 protons to neutrons to be stable protons to neutrons to be stable 1 3.5 4 4.5 5 5.5 6 � As we add or subtract neutrons, atoms � As we add or subtract neutrons atoms As we add or subtract neutrons, atoms As we add or subtract neutrons atoms energy (MeV) gy ( ) decay energy versus half-life for beta-gamma emitters decay energy versus half life for beta gamma emitters become unstable (radioactive) become unstable (radioactive) 1.E+11 1.E+09 � As the neutron excess (or deficit) As the neutron excess (or deficit) 1.E+07 1.E+05 half-life (yrs) increases, the half increases, the half- -life decreases and the life decreases and the 1.E+03 1.E+01 decay energy increases decay energy increases 1.E-01 0 1000 2000 3000 4000 5000 6000 7000 1.E-03 1.E-05 1.E-07 decay energy (KeV) What’s an isotope/nuclide What’s an isotope/nuclide Examples Examples � An atomic nucleus contains protons and An atomic nucleus contains protons and � C- -12 12 neutrons neutrons � � C- -14 14 � The number of protons determines which The number of protons determines which � chemical element is present chemical element is present chemical element is present chemical element is present � P-32 P 32 32 32 � � Co Co- -60 60 � A nucleus may have different numbers of A nucleus may have different numbers of � neutrons neutrons � Cs Cs- -137 137 � � Each different number of neutrons with the Each different number of neutrons with the � U- -235 235 � same number of protons is a different same number of protons is a different � U- -238 238 � isotope (or nuclide) of that element isotope (or nuclide) of that element 3
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