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Radioisotope Laboratory Safety UCSC. Conrad Sherman x9-3911 RSO/Health Physicist Marcus Balanky x9-5167 ARSO/ Health Physicist Vern Ares x9-5167 Assistant Health Physicist Environmental Health & Safety Radiation Safety (831) 459-3911 Environmental Health & Safety Radiation Safety
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Radioisotope Laboratory SafetyUCSC Conrad Sherman x9-3911 RSO/Health Physicist Marcus Balanky x9-5167 ARSO/ Health Physicist Vern Ares x9-5167 Assistant Health Physicist Environmental Health & Safety Radiation Safety (831) 459-3911 Environmental Health & Safety Radiation Safety (831) 459-3911 University of California, Santa Cruz
Radiation Safety University of California, Santa Cruz
Training Requirements* Academic training : • Principles and practices of radiation protection • Radioactivity measurements, monitoring techniques, and using instruments • Mathematics and calculations basic using and measuring radioactivity • Biological effects of radiation. • Appropriate on-the-job-training: • Observing authorized personnel using survey equipment, collecting samples, and analyzing samples • Using survey equipment, collecting samples, and analyzing samples under the supervision and in the physical presence of an individual authorized to perform surveys. * NUREG 1556 Volume 11 Appendix S University of California, Santa Cruz
You are here University of California, Santa Cruz
A Banana Slug University of California, Santa Cruz
Required reading University of California, Santa Cruz
What is the purpose of safety training? To increase your knowledge to enable you to perform your job safely by adhering to proper radiation protection practices while working with or around x-ray generating devices. University of California, Santa Cruz
Radiation Units • Roentgen (R)The roentgen (R) is a unit of radiation exposure in air. • It is defined as the amount of x-ray or g radiation that will generate 2.58E-4 coulombs/kg of air at standard temp and pressure. • radRAD stands for Radiation Absorbed Dose and is the amount of radiation that will deposit 0.01 J/kg of material. • A roentgen in air can be approximated by 0.87 rad in air, 0.93 rad in tissue, and 0.97 rad in bone. • Dose • The SI unit of absorbed dose is the gray (Gy), which has the units of J/kg. 1 Gy= 100 rad. University of California, Santa Cruz
Radiation Units • REMREM stands for Roentgen Equivalent Man. The REM is a unit of absorbed dose and is equal to the rad multiplied by a weighting factor which varies according to the type of radiation. The weighting factor for x-rays is equal to 1. • For x-rays, one rem is equal to one rad. • The SI unit used in place of the rem is the sievert (Sv). 1 Sv = 100 rem. University of California, Santa Cruz
Radiation Sources • X-ray diffraction is a source of very intense radiation. • The primary beam can deliver as much as 400,000 R/minute • Collimated and filtered beams can produce about 5,000 to 50,000 R/minute • Diffracted beams can be as high as 80 R/hour University of California, Santa Cruz
Fundamental Radiation Physics • Radioactivity – spontaneous nuclear transformations • Generally alpha particles and beta particles • Often accompanied by gamma ray emission • Radiation – alpha particles, beta particles, gamma rays, etc. • Ionizing Radiation – radiation capable of producing charged particles (ions) in the material through which it passes University of California, Santa Cruz
Four principal kinds of ionizing radiation University of California, Santa Cruz
Radiological Fundamentals The basic unit of matter is the atom. Nucleus Electron Nucleus Neutrons Protons University of California, Santa Cruz
X-RAY AND GAMMA ( ) RAY PROPERTIES Cloud & Charge: None Mass: None Velocity: 3 x 108 m/s Origin: Rays: Nucleus X Rays: Electron Bremsstrahlung University of California, Santa Cruz
General Radiation • Radiationis energy in transit in the form of high speed particles and electromagnetic waves. We encounter electromagnetic waves every day. They make up our visible light, radio and television waves, ultra violet (UV), and microwaves with a spectrum of energies. These examples of electromagnetic waves do not cause ionization of atoms because they do not carry enough energy to remove electrons from atoms. University of California, Santa Cruz
General Radiation • Ionizing radiationis radiation with enough energy so that during an interaction with an atom, it can remove tightly bound electrons from their orbits, causing the atom to become charged or ionized. Ionizing radiation deposits energy at the molecular level, causing chemical changes which lead to biological changes. These include cell death, cell transformation, and damage which cells cannot repair. Effects are not due to heating. University of California, Santa Cruz
Visible Light University of California, Santa Cruz
X-rays on EM spectrum University of California, Santa Cruz
Background Radiation Cosmic - 28 mrem Radon - 200 mrem Diet - 40 mrem University of California, Santa Cruz Terrestrial - 28 mrem
Man-made sources of radiation contribute to the annual radiation dose (mrem/yr). Round trip US by air 5 mrem per trip Building materials - 3.6 Gas range - 0.2 Smoke detectors - 0.0001 Man-made Radiation Cigarette smoking - 1300 Medical - 53 University of California, Santa Cruz Fallout < 1
Dose Limits • EPA Guidance for dose limits • NRC Regulations for dose limits • DOT Regulations for transport • State Agreement States • Licensee Institutional Admin Limits University of California, Santa Cruz
Radiation Worker Whole Body Extremities Skin and other organs Lens of the eye Non-Radiation Worker Embryo/fetus Visitors and Public 5 rem/year 50 rem/year 50 rem/year 15 rem/year 0.5 rem/year 0.5 rem/gestation period 0.1 rem/year Regulatory Limits University of California, Santa Cruz
ALARA Program • As Low As Reasonably Achievable • Responsibility of all employees • Exposures shall be maintained ALARA • Below regulatory limits • No exposure without commensurate benefit University of California, Santa Cruz
Responsibilities for ALARA Ultimately YOU are! Management • To establish a program • Meet regulatory limits Safety Organization • Implementing a program • Run the daily operation Radiation Worker • To follow program University of California, Santa Cruz
General Methods of Protection • Time • Distance • Shielding University of California, Santa Cruz
What are x-rays? • X-rays are photons (electromagnetic radiation) which originate in the energy shells of an atom, as opposed to gamma rays, which are produced in the nucleus of an atom. University of California, Santa Cruz
X-RAY AND GAMMA ( ) RAY PROPERTIES Charge: None Mass: None Velocity: 3 x 108 m/s Origin: Rays: Nucleus X Rays: Electron Cloud & Bremsstrahlung University of California, Santa Cruz
Ionizing Radiation University of California, Santa Cruz
Legal Limits ANNUAL OCCUPATIONAL DOSE LIMITS EXTENAL mRem DEEP DOSE 5,000 EYE DOSE 15,000 SKIN DOSE 50,000 EXTREMITY DOSE 50,000 ORGAN DOSE 50,000 INTERNAL uCi H-3 80,000 C-14 2,000 P-32 900 P-33 8,000 S-35 10,000 I-125 60 ALLOWED LIMIT OF INTAKE (INHALATION-INGESTION) Note: DOSE = INTAKE 5 REMS ALI University of California, Santa Cruz
Pregnancy Policy University of California, Santa Cruz
Ordering Procedures for Radioactive Material University of California, Santa Cruz
Receipt Record • Sign for package on Receipt and Use Log form University of California, Santa Cruz
Receipt and Use Log • Record • Use (%, volume, or activity) • Name • Date • Purpose • Use blank column for other units University of California, Santa Cruz
Waste Tracking Form University of California, Santa Cruz
Laboratory and Material Security Avoids deliberate misconduct • Lock and key storage • Lock lab • Challenge response to unknown intruders University of California, Santa Cruz
Avoid Ingesting Radioactive Material NO • Eating • Drinking • Smoking • Applying Cosmetics • Mouth Pipetting University of California, Santa Cruz
Protective Clothing • Gloves • Lab coat • Eyewear • Pants • Closed toe footwear University of California, Santa Cruz
Instrumentation University of California, Santa Cruz
Liquid Scintillation Counter • Excellent choice for detecting and measuring low energy beta • Not portable - wipe or smears required for radiation survey use • Requires more training to prepare samples and interpret results than other instruments University of California, Santa Cruz