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Radioactive Materials (RAM) Environmental Health Division Minnesota Department of Health (MDH). Radiological Issues: An Overview. Presentation. Objective: to increase awareness and understanding of key radiation concepts and terminology Research Findings
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Radioactive Materials (RAM) Environmental Health Division Minnesota Department of Health (MDH) Radiological Issues: An Overview
Presentation Objective: to increase awareness and understanding of key radiation concepts and terminology • Research Findings • Basic Radiation Principles • Common Uses • Measurement and Health Effects • Potential Threats • Response • Roles of the MDH
Exposure to radiation can come from the soil, air, and water. True or False? Check what you know! T F T F
As Low As Reasonably Achievable (ALARA) principles are primarily used to protect the public. True or False? T F T F
In a radiation emergency, MDH staff would help recommend protective actions for the public, such as evacuate, shelter in place, or relocate. True or False? T F F T
Amounts of radioactive, biological, and chemical agents all can be measured right away. True or False? T F T F
Three basic safety factors to protect yourself from radiation are distance, shielding, and time. True or False? T F T F
Exposure to radiation can come from the soil, air, and water. ALARA principles are primarily used to protect the public. In a radiation emergency, MDH staff would help recommend protective actions for the public, such as evacuate, shelter in place, or relocate. Amounts of radiation, biological, and chemical agents all can be measured right away. Three basic safety factors in protecting yourself from radiation are distance, shielding, and time. True or False… Summary T F F T T
CDC Research Findings: Medical professionals need more information. http://www.bt.cdc.gov/radiation/pdf/hospitalroundtablereport.pdf, accessed 12/22/2004
Basic Radiation Principles Radiation is energy released from unstable elements. The energy is released until the element is stable. This may take a fraction of a second or billions of years depending upon the element.
Basic Radiation Principles… continued… Decay (decrease in the radioactivity) can be determined using half-lives. A “half-life” is the time it takes for an isotope to reduce its activity by one half…
Basic Radiation Principles … continued… This means that if, an element has a half-life of five years: 1/2 of the radiation would be present in 5 years 1/4 of the radiation would be present in 10 years 1/8 of the radiation would be present in 15 years 1/16 of the radiation would be present in 20 years 1/32 of the radiation would be present in 25 years
Basic Radiation Principles … continued… U-238 has a 4.47 billion year half-life Cesium-137 has a 30 year half-life Cobalt-60 has a 5 year half-life Iodine-131 has an 8 day half-life Other sources of ionizing radiation may decay faster, causing less exposure. Source: http://www.epa.gov/radiation/radionuclides/ accessed 12/23/2004
Basic Radiation Principles … continued… Radiation is everywhere, coming from: • the solar system • the atmosphere • the earth (soil, rocks, and water) and • man-made sources. You cannot see, smell, or feel it.
Basic Radiation Principles … continued… Types of radiation include: Alpha () and Beta () Particles and Gamma () and X-rays
Basic Radiation Principles … continued… • Alpha (a) particles can be blocked by a piece of paper. • Beta (b) particles can be blocked by a firefighter’s turnout gear, but not a piece of paper. • If exposed, wash off particles well with soap and water in a timely manner. • Note: If particles are ingested, inhaled, or enter the body through wounds, medical attention is recommended.
Basic Radiation Principles … continued… Gamma rays (g) are a different matter. • Pure energy, similar to x-rays • Can be blocked by concrete, lead or steel • If exposed, medical attention is recommended.
Remember 3 Factors to Minimize Exposure • Time • Distance • Shielding
Measurement The term used to measure radiation doses is “rem.” It measures the effect of radiation on living tissue, also known as a “biologically effective dose.” Typically, exposure is expressed in “millirems” (mrem) which is one-thousandth of a rem.
Typical Radiation Doses Flight from Los Angeles to London . . . . 5 mrem Annual public dose limit . . . . . . . . . . .100 mrem Annual natural background . . . . . . 300 mrem Fetal dose limit . . . . . . . . . . . . . . . . . 500 mrem Annual radiation worker dose limit . 5000 mrem Emergency:The MDH accepts an emergency exposure for lifesaving only of 25 to 100 rem. Note: Workplace exposures required to be “As Low As Reasonably Achievable” (ALARA)
Radiation Risk Perspective Background Exposure 360 mrem Known Exposure Risks Risks “Annual Occupational Exposure Limit” 5 Rem 0 0.3 5 10 Exposure (in Rem)
Factors that Influence Health Effects of Radiation • General health of the individual • Amount (The “threshold dose” means that the effect is not seen until the absorbed dose is greater than a certain level.) • Frequency (acute or somatic) • Strength of isotope • Targeted cells or organs receiving the dose
Biological Effects of Acute Whole Body Radiation Exposure Risks increase with exposure Death Acute Radiation Sickness Hair loss in 3-4 weeks. Death likely for 50% of exposed and untreated Risks Mild radiation sickness: nausea, fatigue, weak Chromosome errors, burns, not visibly ill ⇝ ⇝ 0 0.3 50- 150 150- 400 400- 600 600- 1500 5000 + Exposure (in Rems)
Uses of radioactive material Medical applications include: • Nuclear medicine equipment • Isotopic generators • Therapy units and seed implants • Radiopharmaceuticals • Computed Tomography (CT) imaging Source: FDA, Center for Devices and Radiological Health http://www.pueblo.gsa.gov/cic_text/health/fullbody-ctscan/fullbody-ctscan.htm Accessed 12/21/2004
Uses of radioactive material Business applications include: • Luminous dials • Moisture and density gauges • Thickness gauges • Rifle sights • Static eliminators Source: Nuclear Regulatory Commission http://www.nrc.gov/reading-rm/doc-collections/news/2004/04-004i.html Accessed 12/21/2004
Uses of radioactive material Public health applications include: • Food irradiation • Radiography • Well logging • Chemical agent detectors • XRFs for lead paint analysis • Smoke detectors http://www.foodprocessing-technology.com/projects/sure/accessed 12/21/2004 Source: FDA, Center for Devices and Radiological Health http://www.pueblo.gsa.gov/cic_text/health/fullbody-ctscan/what.htm accessed 12/21/2004
Potential Radiological Incident? Accidental (Controlled by regulatory systems) • The transportation sector (vehicle, rail, ship) carries many materials across the US. Despite fears of an attack, the most likely radiological incident remains a transportation accident involving radioactive materials. • Nuclear power plants build strong structures and exercise Intentional (Controlled by legal systems) • Stolen materials • Dirty bombs
Damage to a nuclear power plant is difficult to imagine US plants: 3 barriers between radioactive materials and the environment. The reactor will not explode. Structures that house reactor fuel are robust. Fuel is protected from impacts of large commercial aircraft.
Damage to a nuclear power plant is difficult to imagine…continued… Professionals discuss, plan, and perform “exercises” often to rehearse skills and test possible scenarios: • At worst, could be a release of radioactive materials into the air, creating a “plume.” • May need to evacuate a surrounding area. • Precautionary medical measures may be necessary for those caught in the plume or its expected path down-wind.
Bombs with radioactive material (“Dirty Bombs” or “RDDs”) Definition: a conventional bomb surrounded by or filled with non-nuclear radiological materials. (also called a radiological dispersal device, or RDD) Unlikely, and most probable, form of radiological terrorism Radioactivity would not kill or seriously injure people (but an explosion might). Would create fear or chaos: coined a “Weapon of Mass Disruption.” Expect significant long-term psychological effects.
Bombs with radioactive material …Continued… An RDD could be • any size, • spread radiation, and • contaminate an area. This photo was staged, but several alleged real-life RDD plots have been upset. Photo: www.seattle.gov/mayor/gallery_2003/gallery_TOPOFF2_03.htm Erik Stuhaug, photographer, accessed 11/10/2004
Responding to an Incident Remember, a “dirty bomb” will probably not cause radiation sickness or death. • Be alert for secondary attacks, like explosive devices.
Responding to an Incident…continued… • Don’t make a victim of yourself. • No eating. • No smoking. • Wear protective clothing – including double gloves (if available). • Do not move items at the scene. They are evidence.
Responding to an Incident…continued… • Work within an Incident Management System. (Take the free online IMS course: www.sph.umn.edu/umncphp/Incident_Management_Systems.html ) • Incident Commander makes sure the Minnesota Duty Officer has been called and knows the situation and needs: Metro Area ………..(651) 649-5451 Toll Free (MN)..…1 (800) 422-0798
Responding to an Incident … Options to protect the public 1) Save lives 2) Control access 3) Monitor radiation 4) Decontaminate 5) IC communicates action to the public …Evacuate.. or.. Shelter in place 6) Place controls on food and water 7) Relocate…Populations may mass in your jurisdiction for a long time
Public Safety response • 1st responders save lives. Rescue known living victims. • 1st responders control access • Measure contamination levels in and near danger zones. Set up barriers. • Only professional responders enter danger zones. Measure exposures.
Public Safety response …continued… 3) Continue to monitor radiation levels • Responders monitor both cumulative dose and dose rate when in a contaminated area. • Responders consult with state and federal technical experts when setting and adjusting boundaries. Photo: www.seattle.gov/mayor/gallery_2003/gallery_TOPOFF2_03.htm Erik Stuhaug, photographer, accessed 11/10/2004
Public Safety response …continued… 4) Decontaminate: • 1st Responders establish a field decontamination zone in a safe area. • If possible, decontaminate victims and emergency responders before transporting to a hospital. Source: MDH, An Exercise, Courtesy of D Grundmanis
Evacuate..or.. Immediate/urgent removal of people from a contaminated area. Mass shelter and care will be required. Shelter in place Stay indoors, close/ seal doors and windows. Turn off/ cover fans and air conditioners. Individuals must care for themselves. Public safety and public health staff can plan cooperatively. Check your local plans for your role(s). e.g., Communication Plan:Form a JPIC. Present regular PIO briefings and press releases. Media informs the public. Hotline message instructs area residents to:
Public health staff can assist and guide protective actions • Food and drinking water may be sampled, assessed, and controlled. • Relocation… Populations may mass in your jurisdiction for a long time, requiring • safe shelter, • sanitary conditions, • medical care, and • systems or community behavior change. Public health staff will likely play a large role in recovery efforts.
Role of the MDH for Accident Assessment • Assist with development of guidanceto local public officials for: - emergency workers, - remediation personnel, and - the public • Coordinate sampling activities, including air samples
Role of the MDH for Accident Assessment • Analyze samples at the MDH Public Health Laboratory • Review results of sample analysis and make recommendations for protective actions, additional sampling, control, and mitigation as appropriate.
Role of the MDH for Accident Assessment • Develop and maintain a preparedness and response plan for public health aspects of disasters and emergencies
Using the Monitoring Equipment Unlike many biological or chemical agents, the presence and amount of radiation can be detected immediately. Photo: Fred Hutchinson Cancer Research Center , 10/16/2003 http://www.fhcrc.org/pubs/center_news/2003/oct16/Radiation.jpg Accessed 1/3/2005
Using the Monitoring Equipment …continued… Stop. Look. Listen. Anytime an incident is reported that could be remotely perceived as terrorism, the first responder should take a Geiger counter. Approach the site cautiously with the survey meter on the lowest scale. (There normally are some slow clicks measuring background radiation. But if it clicks faster, there is more radiation.)
Using the Monitoring Equipment …continued… There are two primary uses for a Geiger counter: 1) To identify radiation levels 2) To identify contamination on personnel, equipment, and property