410 likes | 672 Views
Radiation Safety. Edward O’Connell Radiation Safety Officer Stony Brook University New York. STONY BROOK UNIVERSITY & U. HOSPITAL MEDICAL CENTER. Why Radiation Safety. Working with radioactive material is not a University right but a privilege in NYS
E N D
Radiation Safety Edward O’Connell Radiation Safety Officer Stony Brook University New York
STONY BROOK UNIVERSITY & U. HOSPITAL MEDICAL CENTER
Why Radiation Safety • Working with radioactive material is not a University right but a privilege in NYS • Licensing Permit issued through NYSDOH/Bureau of Environmental Radiation Protection (BERP) • Regulatory Compliance – State Sanitary 16 • Required Radiation Safety Program • Radiation Protection Philosophy - ALARA
What is Radiation? • Radiation is Energy • Two Types: • Non-Ionizing Radiation • Ionizing Radiation
The ability of electromagnetic radiation to cause ionization depends on the energy
Units of Measurements Radioactivity: Curie Exposure: Roentgen (R) Dose: rad Dose Equivalent: rem 1R = 1rad = 1rem (for x-rays in soft tissues)
Sources of Background Radiation Exposure • Naturally occurring radioactive materials. • Cosmic radiation. • Fall-out from nuclear weapons tests. • Medical exposures. • Occupational exposure.
Radiation Dose From Background Radiation • The dose received by the general public varies by location. • At sea level, on the east coast of the U.S., The dose to the general public is about300 millirem per year. • At 50,000 feet, the dose rate is about1 millirem per hour. • There are areas in the world where the average background is 1,000 millirem per year.
AT STONY BROOK UNIVERSITY HOSPITAL • Radiation Therapy, 2nd floor SBUH • Laboratories, 3rd floor SBUH • Radiology, 4th floor SBUH • Nuclear Medicine, 4th floor of the Hospital • Cardiology, 5th floor of the Hospital • Mobile PET/CT unit, outside adjacent to the MRI suite. • There are also x-ray units at most of the outpatient facilities and Nuclear Medicine suites at Tech Park and Islandia.
At Stony Brook University • Life Sciences & CMM • HSC – Clinical and Basic • Dental School • MSRC • Engineering/ Grad Physics/ Grad Chem • LIHTI • Psych A & ESS
Regulatory Limits • Whole Body: 5 rem per year • Extremities: 50 rem per year • Any single organ: 50 rem per year • Lens of the eye: 15 rem per year • Fetus: 0.5 rem during the gestation period • Non – occupationally exposed persons:0.1 rem per year • Average SBU authorized user exposure < .050 rem/yr or 50 mRem/yr (note Bkg radiation = 300 mRem/yr & Medical / Dental X-ray contributes = 65 mRem/yr))
Biological Effects Short – Term Effects Long – Term Effects
Short – Term Effects • Skin effects • Hemopoietic effects • Gastrointestinal effects • Neurological effects • Effects on the fetus
Long – Term Effects • Increased risk of developing cancer • Damage to genetic material • Formation of cataracts • Damage to the skin
RADIATION WORK AS A “SAFE PROFESSION” • The Regulatory Limits were established to make the risk of death from exposure to radiation in the workplace similar to the risks of death in “safe” professions. • The “safe professions” are: • Finance • Service • Retail Trade
Radiation Protection Instrumentation • Unlike many other hazards, ionizing radiation is relatively easy to detect. • Several types of instruments are used to detect and quantify ionizing radiation: • Survey meters • Personnel monitors
Personnel Monitors • Monitor individual doses • Monthly &/or Bi-monthly reports reviewed and mailed out by the RSO • ALARA investigational levels are set with follow-up on • Annual Individual report mailed out by the RSO to all badge holders • Each area has a film badge coordinator
Radiation and the Law • Federal: F.D.A. and N.R.C. • State: N.Y.S. Dept. of Health • Local: Suffolk County Dept. of Health • University Radiological Protection Committee (URPC) • U. Hospital Medical Center Radiation Safety Committee
ALARAAs Low As Reasonably Achievable Minimize Exposure to Minimize Risk See Handout = 10 Principles & 10 Commandments for Radiation Protection
Practical Means of Personal Protection • Time • Distance • Shielding • Good working habits
Time The total dose depends upon the dose rate. Minimizing the time minimizes the dose.
Distance The Inverse Square Law works! Maximize distance to minimize dose.
Shielding Use shielding whenever possible. ½ “ Plexi Glass shields stop all P-32 beta radiation A lead apron reduces the exposure by as much as 95%
Good Working Habits Good working habits are the key to minimizing everyone’s dose.
MRI SAFETY The next few slides discuss MRI Safety
Non-Ionizing Radiation Safety MRI SAFETY • Remember that the magnet is always “on”. • Metal objects can be pulled in to magnet • Magnetic field can interfere with pacemakers and monitoring devices • Only authorized persons should enter the magnet room • Patients are escorted by MRI staff
Metal objects can be pulled away from you and into the magnet.
Contacts • Edward O’Connell – University RSO 632-9674 • Hospital RSO -- 444-3196 • Medical Physics -- 444-8228