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Environmental Laboratory Accreditation Course for Radiochemistry

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1 Environmental Laboratory Accreditation Course for Radiochemistry
Presented by Minnesota Department of Health Pennsylvania Department of Environmental Protection U.S. Environmental Protection Agency Wisconsin State Laboratory of Hygiene

2 About this course This radiochemistry course was coordinated by Susan Wyatt of the MN Dept of Health Environmental Laboratory Certification program in to fill an existing gap in the USEPA certification officer’s training course. The course was presented in three locations nationwide beginning in Minnesota in September 2006; then Pennsylvania in December 2006; and finally, Arizona in February 2007.

3 The instructors Jeff Brenner, MN Dept of Health
Michella Karapondo, USEPA John Lorenz, MN Dept of Health Richard Sheibley, PA Dept of Env Protection Lynn West, WI State Lab of Hygiene Susan Wyatt, MN Dept of Health

4 Course Organization Pre Test: basic knowledge 3 ½ days instruction
USEPA requirements Radiation theory & safety Radiochemistry instrumentation, & methods PT samples Data review

5 Course Objectives Gain knowledge sufficient to assess laboratories
NELAC compliance USEPA SDWA compliance Nurture awareness of newer radiochemistry technologies and methods

6 U.S. Environmental Protection Agency
Recent Legislation Michella Karapondo U.S. Environmental Protection Agency

7 Drinking Water Program Update
December 2006 OGWDW, TSC

8 Office of Ground Water and Drinking Water
What do we do? Develop drinking water regulations Set drinking water standards Proficiency testing criteria Approve drinking water methods Evaluate and develop analytical methods Alternate testing procedures (ATPs) Implement laboratory certification program Radiochemistry audits NELAC

9 National Environmental Laboratory Accreditation Conference (NELAC)
OGWDW endorsement of NELAC 2002 letter from OGWDW supports use of NELAC standard Drinking water accreditation must be as stringent as USEPA’s certification Certification by method AND analyte vs. technology/analyte or analyte group Drinking water requires use of defined methods Performance based methods are NOT ALLOWED! New methods allow for some laboratory flexibility

10 Proficiency Testing (PT) Program for Drinking Water
NIST/NVLAP A2LA Accredits providers EPA -set standards USEPA Criteria Document Laboratories Analyze PT Samples PT Providers Conducts PT Studies CO/AA - Reviews PT Results Note that EPA terminology is different – Performance Evaluation – PE Study

11 Where can I find PT criteria?
Regulatory acceptance limits are in the CFR Called “Performance Evaluation” in the CFR Inorganic criteria: 40 CFR (k)(3)(ii) VOC criteria: 40 CFR (f)(17)(i) and (ii) for vinyl chloride SOC criteria: 40 CFR (f)(19)(i)(B) Lead/copper criteria: 40 CFR (a)(1)(ii)(A) and (B) DBP criteria: 40 CFR (b)(2) – NOTE that the 2005 CFR does not have the updated DBP criteria! NELAC FoPT Tables

12 Radiochemistry Audits for EPA Region, State and Tribal Laboratories
TSC currently supports through extramural monies State laboratories needing certification are currently audited using a contractor May not be an option in the near future We are working with the regions to find alternate funding

13 Drinking Water Methods
Developed by TSC and ORD Other government agencies USGS Review methods from voluntary consensus method standard bodies ASTM, Standard Methods, AOAC Approved through the regulatory process

14 Evaluating Methods: The Alternate Testing Program
40 CFR allows “alternate analytical techniques” MUST have written permission from EPA A letter from EPA OR Publication in the Federal Register ATPs are national – there are no lab specific ATPs for drinking water For drinking water protocol, call Sample Control Center at Questions? Contact

15 Alternate Testing Program (ATP)
ATP letters will be posted on OGWDW’s web site

16 Where can I find approved methods?
Approved methods are listed in CFR Inorganic methods: 40 CFR Organic methods: 40 CFR Methods for radioactivity: 40 CFR Lead and copper: 40 CFR Disinfection by-products: 40 CFR BUT, the CFR is published only once a year! Keep an eye on the Federal Register! Approved methods are listed on OGWDW’s web site Some EPA methods are available in PDF format National Environmental Monitoring Index (NEMI)

17 National Environmental Monitoring Index (NEMI)
Database of methods applicable for monitoring water for chemical and microbiological pollutants Useful for comparing/contrasting methods Caution! NEMI may not always contain correct/approved version of method Can search by analyte, matrix, CAS number, and/or regulatory requirement Public release October 2002 – announced by joint USGS/USEPA letter

18 NEMI Search – General

19 NEMI Search – By Regulation

20 Safe Drinking Water Act (SDWA)
Authorizes EPA to set enforceable health standards for contaminants in drinking water affects all public water systems serving at least 25 people or having at least 15 service connections required that the National Primary Drinking Water Regulations be drafted amended in 1977, 1979, 1980, 1986, and 1996 (reauthorized and amended).

21 How does OGWDW decide what to regulate?
1996 SDWA amendments changed the process Contaminant Candidate List (CCL) Unregulated Contaminant Monitoring (UCMR) Regulatory Determination Regulatory Promulgation Regulatory Implementation Six Year Review

22 Regulations Proposal Public Comment Final Rule

23 Federal Register Published daily by the Office of Federal Register (National Archives and Records Administration – NARA) Notices, Proposed & Final Rules Preamble An explanation of rule Contact person Docket information How to submit comments (for proposed rules) Rule The legal requirements Only lists changes Available on line at

24 Preamble to Proposed Methods Update Rule
FR Citation (69 FR April 6, 2004)

25 Language in Proposed Methods Update Rule
FR Citation (69 FR April 6, 2004) * * * Indicates no change in current rule language

26 Dockets Proposed rule dockets contain supporting documents & public comments Final rule docket also has Agency response to public comments Docket number is listed in preamble Electronic access to dockets at:

27 Want to know when something is published?
Subscribe to EPA’s ListServer to receive an when a FR is published relating to “water” https://lists.epa.gov/read/all_forums/

28 Code of Federal Regulations (CFR)
Codification of Federal Rules Rule language (no preamble) 50 titles - Drinking Water is Title 40 Published volumes are updated annually Title 40 is updated on July 1 Incorporates all changes from previous year Available on line at e-CFR updated frequently (not official version)

29 Radionuclides in Drinking Water
First radionuclide regulations promulgated Amendments to SDWA 1991 – Proposed regulations and revisions 1996 – Amendments to SDWA 2000 – Final radionuclide rule

30 Analytical Methods for Radionuclides 62 FR 10168 – March 5, 1997
Approved the use of 66 radionuclide methods 54 methods proposed in the 1991 radionuclide proposed rule 12 methods from public comments to that proposal Full list of approved radionuclide methods in 40 CFR

31 Radon 64 FR 59246 - November 2, 1999 – Proposed Rule
Will apply to community water systems using ground water or mixed ground and surface water Multi-Media Mitigation program plans to address indoor air along with water Rn-222 MCL = 300pCi/L or AMCL = 4,000pCi/L first application of AMCL and MMM Final rule 2007 or 2008 (or longer!)

32 Radionuclide Rule 65 FR 76708 - December 7, 2000 - Final Rule
Retains previously regulated radionuclide contaminants and adds requirements for Uranium Applies to community water systems Initial monitoring complete by December 31, 2007 Sets a new MCL for Uranium – 30 ug/L Retains the existing MCLs for: Radium-226/228 – 5 pCi/L Gross alpha particle radioactivity – 15 pCi/L Includes Ra-226, but excludes radon and uranium Beta particle and photon activity – 4 mrem/yr Set all Maximum Contaminant Level Goals (MCLGs) for radionuclides at 0 pCi/L

33 Analytical Method for Uranium 69 FR 52176 - August 25, 2004
Approves three ICP-MS methods for Uranium EPA 200.8, revision 5.4 SM 3125 (20th edition) ASTM D

34 Method Update Rule 69 FR 18166 – April 6, 2004 – Proposed Rule
OGWDW and OST Updated versions of ASTM & SM methods Too many to list here ATP methods Micro ATP Protocol EPA 327 – Chlorine dioxide Proposed withdrawal of Atrazine immunoassay Georgia Tech method for the determination of Ra-226 and Ra-228 by Gamma-ray Spectrometry Final rule – 2006

35 Footnote 14: "The Determination of Radium-226 and Radium-228 in Drinking Water by Gamma-ray Spectrometry Using HPGE or Ge(Li) Detectors," Revision 1.2, December Available from the Environmental Resources Center, Georgia Institute of Technology, 620 Cherry Street, Atlanta, GA , USA, Telephone: This method may be used to analyze for radium-226 and radium-228 in samples collected after January 1, 2005 to satisfy the radium-226 and radium-228 monitoring requirements specified at 40 CFR

36 Resources OGWDW Website http://www.epa.gov/safewater
Drinking Water Regulations Laboratory Certification Lab Cert Manual as PDF Federal Register

37 Resources PT Tables http://www.epa.gov/nelac/pttables.html
Drinking Water Methods NEMI Radionuclide page

38

39 Implementation: USEPA Drinking Water Certification Program
Michella Karapondo U.S. Environmental Protection Agency

40 Topics Authority for certification program
Program structure and responsibilities Certification process and criteria .

41 Safe Drinking Water Act (SDWA)
Authorizes EPA to set enforceable health standards for contaminants in drinking water affects all public water systems serving at least 25 people or having at least 15 service connections required that the National Primary Drinking Water Regulations be drafted amended in 1977, 1979, 1980, 1986, and 1996 (reauthorized and amended).

42 Required By 40 CFR “… Samples may be considered only if they have been analyzed by a laboratory certified by the state except that measurements for alkalinity, calcium, conductivity, disinfectant residual, orthophosphate, pH, silica, temperature, and turbidity, may be performed by any person acceptable to the state.”

43 Primary Enforcement Responsibility 40 CFR 142.10
A State has primacy when… it has adopted drinking water regulations no less stringent than the Federal regulations it has adopted and implemented adequate procedures for enforcement of State regulations inventory of systems sanitary surveys establishes and maintains a certification program and designates a CPM certified by the Administrator responsible for the State certification program

44 USEPA Drinking Water Laboratory Certification Program
Program began in 1978 Hierarchical structure Fundamentals are in the “Lab Cert Manual” Accept NELAP accreditation

45 Certification Program Structure
USEPA Office of Ground Water and Drinking Water Regional Laboratory/Certification Program State Laboratory & Certification Program Private Laboratories

46 Certification Officers
Should have a college degree in the discipline for which they certify and have recent laboratory experience Should have experience in lab evaluation and quality assurance Successfully complete EPA's Certification Officers training course

47 Scope of Certification
Certification is granted in three areas: Chemistry Microbiology Radiochemistry

48 Certification Process
Lab requests (re)certification Lab passes PT sample Lab certified for 3 years On-site audit performed Set date for on-site audit

49 On-site Evaluation Items
Are promulgated/approved methods being used and requirements of those methods met Are appropriate quality systems in place Are personnel qualified and sufficient Are laboratory facilities, equipment and supplies adequate Data audit

50 Types of Certification
Certified Provisionally certified Not certified Interim certification

51 Certified Laboratory meets the regulatory performance criteria by:
using promulgated/approved methods demonstrating successful performance on proficiency testing (PT) samples by analyte and method on an annual basis passing an on-site audit at least every 3 years Must notify Certification Authority of any major changes (personnel, equipment, facility)

52 Provisional Certification
Laboratory has minor deficiencies but is still able to consistently produce valid data using promulgated/approved methods insufficient/incomplete documentation failed PT samples

53 Provisional Status May continue to analyze compliance samples; however: Must notify clients of status For a limited time -- follow up is needed to ensure corrective actions have been completed or lab should be decertified

54 Not Certified Laboratory possesses deficiencies and cannot consistently produce valid data has a lack of equipment/personnel makes changes in method(s) that are not allowed is unresponsive to deficiencies found resulting in provisional certification

55 Interim Certification
Impossible or unnecessary to perform an on-site audit for new contaminants when no PT sample is available when constraints prevent a timely on-site audit Lasts until next scheduled on-site or a PT sample is available

56 More Drinking Water Lab Cert Information
OGWDW Web site TSC Lab Cert Team addresses: (micro)

57 Web Sites Laboratory Certification Manual, 5th Edition:
Methods (listed by contaminant/method number): CFR: DW REGS: List of state certified labs: Proficiency Testing Samples:

58 Richard Sheibley Pennsylvania Dept of Env Protection
Proficiency Testing Richard Sheibley Pennsylvania Dept of Env Protection

59 Proficiency Testing Requirements
At least one successful PT study per year (two PTs per year for NELAC compliance) for the following: Strontium 89 Strontium 90 Gamma Barium 133 Cesium 134 Cesium 137 Cobalt 60 Zinc 65 Iodine 131 Gross alpha Gross beta Tritium Radium 226 Radium 228 U (natural)

60 PT Study Activity Ranges

61 PT Study Acceptance Criteria

62 PT Vendor information

63 Most common lab deficiencies for Rad PTs

64 PTs in other matrices/quality control stds

65 Radiochemistry Theory
John Lorenz Minnesota Department of Health Public Health Laboratory

66 What we’ll cover What radiation is Types of radiation
What radioactive material is Characteristics of radioactive material and radiation How these characteristics affect analytical methods MCLs and analysis (counting)

67 Basics Of Radiation

68 RADIATION IS ENERGY TRAVELING THROUGH SPACE IN THE FORM OF WAVES OR PARTICLES
LIGHT MICROWAVES HEAT Radiation is __________________ moving through space in the form of __________ or ______________ NUCLEAR RADIATION

69 } } IONIZING vs. NON-IONIZING NON-IONIZING IONIZING LIGHT MICRO- WAVES
HEATING HEAT - } Radiation having enough energy to knock ______________ out of orbit is known as _______________ radiation. IONIZATION NUCLEAR RADIATION IONIZING +

70 Ionization Ionization causes health risks Ionization allows detection
_____________ _____________ use ionization to do analysis.

71 Radioactive Material

72 Radioactive Material - Atoms
Nucleus with protons and neutrons Orbiting Electrons The atom is made up of a central ______________ and orbiting ________________.

73 Radioactive Material – Unstable Nuclei
Improper balance of protons and neutrons in nucleus Excess energy A nucleus with too many neutrons or protons is ____________________.

74 Radioactive Material – Unstable Nuclei
Reaches balance by giving off particles or energy waves or both Radioactive Material  Radiation The change of nuclear structure is called nuclear disintegration To reduce the excess ________________ in the nucleus, it emits radiation.

75 Radioactive material Atoms emitting radiation are radioactive material
A specific type of radioactive material is called a radionuclide ___________________________ _____________________ is made up of atoms that emit radiation. A specific type of radioactive material is called a __________________.

76 Radioactive material Atoms emitting radiation are radioactive material
A specific type of radioactive material is called a radionuclide Radium-226 Radium-228 Uranium-238 Strontium-90 Hydrogen-3 Isotopes of Radium Radionuclides of the same element with different masses are _______________.

77 Radionuclides can be represented in alternative ways
Radioactive material Radionuclides can be represented in alternative ways 226Ra = 226Ra = Ra-226 228Ra = 228Ra = Ra-228 239U = 239U = U-238 90Sr = 90Sr = Sr-90 3H = 3H = H-3(Tritium) 88 88 Radionuclides of the same element with different masses are _______________. 92 38 1

78 Uranium Decay Series a a a b a b a a a b b b a b Th-230 77,000 y
Rn-222 3.8 d b Pa-234m 1.2 m Po-218 3.1 min a a Th-234 24 d a b Uranium samples frequently contain other radioactive materials because of the many radionuclides in the uranium decay series. When a sample containing Radon-222 is collected, its _______________ _______________ quickly reach secular equilibrium. Pb-214 26.8 min Pb-206 Stable Po-210 138 d Bi-214 19.9 min b b U-238 4.5E9 y a b Bi-210 5 d Po-214 160 usec Pb-210 22.3 y

79 Thorium Decay Series b b a a b a a a a b a b Ac-228 6.1 hr Th-228
1.9 yr Ra-228 5.8 yr Th-232 1.4E10 yr b Ra-224 3.7 day a a Pb-208 Stable Tl-208 3.1 min a a Rn-220 56 sec Po-212 310 nsec b a b Po-216 0.15 sec Bi-212 61 min Pb-212 11 hr

80 Types of Radiation Alpha (a) Beta (b) Gamma (g)
There are other types of radiation, such as neutrons, neutrinos and heavy particles, but they are not an important source of exposure in drinking water.

81 ALPHA DECAY ++ NUCLEUS PARTICLE FORM OF RADIATION
An alpha particle is made up of two neutrons and two protons. Because of its double ____________________ charge and its large mass, the alpha particle is ____________ _______________ penetrating. PARTICLE FORM OF RADIATION LOW PENETRATING ABILITY SIGNIFICANT INTERNAL EXPOSURE HAZARD

82 - BETA DECAY NUCLEUS PARTICLE FORM OF RADIATION
A beta particle is an electron ejected from the nucleus. Beta particles are _________________ penetrating. PARTICLE FORM OF RADIATION MODERATE PENETRATING ABILITY PREDOMINANTLY INTERNAL EXPOSURE HAZARD

83 GAMMA DECAY NUCLEUS WAVE FORM OF RADIATION
Gamma rays are very similar to ______________, but with a higher energy. X-rays are indistingushable from gamma rays, except that x-rays originate in the _____________ orbits rather than the ___________________. Gamma rays and x-rays have no mass. WAVE FORM OF RADIATION SIGNIFICANT PENETRATING ABILITY EXTERNAL & INTERNAL EXPOSURE HAZARD

84 Characteristics of Radioactive Material
Activity Half-life (T1/2) Random decay Geometry Ingrowth The varying characteristics of

85 Activity - quantitative
Number of nuclear disintegrations per unit time Disintegrations per second (dps) Disintegrations per minute (dpm) May be more or less than one radiation emission per disintegration Not dependent on temperature or pressure Activity is the number of __________________ ___________________ occurring per unit ______________.

86 Activity Units Curie (Ci)
37 billion (3.7x1010) disintegrations per second Millicurie (mCi = 10-3 Ci) Microcurie (mCi = 10-6 Ci) Nanocurie (nCi = 10-9 Ci) Picocurie (pCi = Ci) 1 pCi = 2.22 dpm Femtocurie (fCi = Ci) A _________________________ is 37 billion disintegrations per second. The MCLs for radioactivity are given in ____________________ per liter.

87 Activity Units Becquerels (Bq) 1 Bq = 27 pCi
1 disintegration per second (dps) Megabecquerels 1 Bq = 27 pCi

88 Activity - quantitative
Proportional to number of atoms of radionuclide Atoms Activity _____________________ increases proportionally with the number of _____________ of the radionuclide.

89 Activity - quantitative
Proportional to number of atoms of radionuclide For Ra-226 1 g 2 g 4 g 1Ci 2 Ci 4 Ci

90 Activity - quantitative
Inversely proportional to half-life T1/2 Activity The relationship between activity and half-life is ___________________ _________________.

91 Half-life (T1/2) The time it takes for half of the radioactive material to decay, or The time it takes for decay to reduce the amount of radioactive material by 50%. Half-life is the time it takes for the quantity of radioactive material to be reduced by ______________ percent.

92 Iodine – 131: Half-life = 8 days
Today Activity = 200 pCi After 8 Days Activity = 100 pCi After 16 Days Activity = 50 pCi

93 Activity - quantitative
Inversely proportional to half-life T1/2 Activity The relationship between activity and half-life is ___________________ _________________.

94 Activity - quantitative
Inversely proportional to half-life For 2.7x1021 atoms 30 y 1600 y 4.5 billion y Ci 1 Ci 53 Ci Cs-137 Ra-226 U-238

95 Half-life (T1/2) T1/2 for commonly used radionuclides
U billion years Cs years Co years P days I days Rn days Ac hours F hours The _____________-_______________ of radioactive materials can range from a fraction of a _________________ to billions of __________________.

96 Half-life - Implications
Decay correction: Accounts for difference from collection until analysis Prompt analysis needed for short half-life nuclides like Actinium-228 (T1/2 = 6.1 hr, surrogate for Ra-228) Decay constant (l) relates activity to half-life l = ln2/T1/2 A = Nl The uncertainty in measurement of the activity increases with time for short half-life radionuclides.

97 Radioactive Decay is Random
Variable decay rate Source of uncertainty in analysis Reduced by longer time Reduced by higher activity 20 - Radioactive decay is a ______________ process. The number of atoms decaying during any period of time will likely not be the same as the number decaying during any other period of the same length. 15 - Decay Rate (dpm) 10 - 5 - 0 - 1:00 2:00 3:00

98 Geometry Refers to the shape and position of the source
Must be consistent for calibration and analysis Geometry refers to the position, shape and distribution of ________________ ______________ within the source.

99 Ingrowth One radionuclide decays to another radionuclide
If decay product has much shorter half-life, its activity will equal parent’s activity The decay product is being produced by the decay of the parent. Eventually, if the decay product has a much shorter half-life than the parent, it will decay as fast as it is produced. The process of the ____________ product’s activity equaling the ______________ activity is known as secular equilibrium

100 Uranium Decay Series a a a b a b a a a b b b a b Th-230 77,000 y
Rn-222 3.8 d b Pa-234m 1.2 m Po-218 3.1 min a a Th-234 24 d a b Uranium samples frequently contain other radioactive materials because of the many radionuclides in the uranium decay series. When a sample containing Radon-222 is collected, its _______________ _______________ quickly reach secular equilibrium. Pb-214 26.8 min Pb-206 Stable Po-210 138 d Bi-214 19.9 min b b U-238 4.5E9 y a b Bi-210 5 d Po-214 160 usec Pb-210 22.3 y

101 Thorium Decay Series b b a a b a a a a b a b Ac-228 6.1 hr Th-228
1.9 yr Ra-228 5.8 yr Th-232 1.4E10 yr b Ra-224 3.7 day a a Pb-208 Stable Tl-208 3.1 min a a Rn-220 56 sec Po-212 310 nsec b a b Po-216 0.15 sec Bi-212 61 min Pb-212 11 hr

102 Ingrowth - Implications
Short half-life decay product as surrogate for longer lived parent (Ra-228  Ac-228) After chemical processing, allowing ingrowth of shorter lived nuclides

103 Characteristics Of Radiation

104 Characteristics of Radiation
Physical form (Particle or wave) Energy (keV or MeV) Charge Mass Penetration Range Attenuation Interactions with matter Velocity

105 ALPHA DECAY ++ NUCLEUS PARTICLE FORM OF RADIATION
An alpha particle is made up of two neutrons and two protons. Because of its double ____________________ charge and its large mass, the alpha particle is ____________ _______________ penetrating. PARTICLE FORM OF RADIATION LOW PENETRATING ABILITY SIGNIFICANT INTERNAL EXPOSURE HAZARD

106 - BETA DECAY NUCLEUS PARTICLE FORM OF RADIATION
A beta particle is an electron ejected from the nucleus. Beta particles are _________________ penetrating. PARTICLE FORM OF RADIATION MODERATE PENETRATING ABILITY PREDOMINANTLY INTERNAL EXPOSURE HAZARD

107 GAMMA DECAY NUCLEUS WAVE FORM OF RADIATION
Gamma rays are very similar to ______________, but with a higher energy. X-rays are indistinguishable from gamma rays, except that x-rays originate in the _____________ orbits rather than the ___________________. Gamma rays and x-rays have no mass. WAVE FORM OF RADIATION SIGNIFICANT PENETRATING ABILITY EXTERNAL & INTERNAL EXPOSURE HAZARD

108 Other Origins for Radiation
Internal Conversion Electron Capture Bremsstrahlung Gamma rays are very similar to ______________, but with a higher energy. X-rays are indistinguishable from gamma rays, except that x-rays originate in the _____________ orbits rather than the ___________________. Gamma rays and x-rays have no mass.

109 Radiation Penetration
alpha beta Alpha particles are the ______________ penetrating form of radiation, and can be stopped by a sheet of paper or dead outer layers of skin. ______________ ___________________ are moderately penetrating and can be stopped by _______________ or __________________. Gamma rays are very ___________________ and require heavy _________________ such as lead, iron or concrete. gamma Paper Lead Plastic

110 Penetration - Implications
a and b - intimate contact with detection medium g emitters can pass through containers and detector housings Self-absorption can occur in material containing radionuclides A sample containing alpha emitters must be ______________ so the alpha particles can reach the sensitive area of the __________________.

111 Self Absorption How absorption related to thickness
affects counting efficiency 3 mg. solids 27 dpm 8 cpm 2 mg. solids 18 dpm 8 cpm 1 mg. solids 9 dpm 5 cpm Detector Detector Detector

112 Energy Each radionuclide emits specific energies.
Energies are expressed in keV or MeV. a and g emitting radionuclides have discrete energies b emitting radionuclides have a continuous spectrum of energies a energies are for the most part distinctly higher than b energies

113 Energy - Implications Energy spectrometry allows identification of a or g emitters Energy “windows” can be set to look at only the energies of interest

114 Gamma Spectrum – fish from North Sea and Irish Sea

115 Beta+ Spectrum From Cu-64

116 Radiation Interactions

117 Ionization

118 Ionization _____________ that are ejected from orbit may cause additional ionization.

119 Radiation interactions
Transfer of energy to electrons a and b particles Continuous interaction through matter Gradual loss of energy Definite range g rays Interactions are probabilistic May transfer all or part of energy

120 Radiation interactions
a and b particles Continuous interaction through matter Gradual loss of energy Definite range e- a e- e-

121 Radiation interactions
g rays Photoelectric, Compton, Pair Production Interactions are probabilistic May transfer all or part of energy e- g g e- e-

122 Radiation interactions - implications
Ionization may result in electrical pulse, light pulse, or electron hole pairs Pulse size proportional to energy released a and b particles All energy released in detector Pulse is proportional to energy of radiation g rays If all energy transferred, pulse is proportional to energy of radiation

123 Drinking Water MCLs

124 MEASURING RADIATION 1 R 1 RAD 1 REM ROENTGEN (R) REM biological dose
the energy of radiation REM biological dose equivalent RAD radiation energy absorbed by any material RADIATION SOURCE 1 R 1 RAD 1 REM

125 AVERAGE ANNUAL EXPOSURE
NATURALLY OCCURRING HUMAN-MADE 70 mREM 300 mREM

126 Basis for Radionuclide MCL’s
Risk is based on amount of radiation, not mass of radioactive material Most concentration limits stated as activity rather than mass. Activity not measured directly Can use radiation emitted to determine the activity.

127 MCL Ra-226 + Ra-228 Ra-226 + Ra-228 MCL = 5 pCi/L Equivalent to:
5x10-12 g/L Ra-226 1.8x10-14 g/L Ra-228

128 MCL – Gross Alpha Gross Alpha Excludes Uranium and Radon
Includes Radium MCL = 15 pCi/L

129 MCL – Uranium Uranium MCL expressed in mass concentration
MCL = 30 ug/L

130 MCL – Man-Made Beta and Gamma Emitters
MCL expressed in exposure to people drinking the water MCL = concentration that would result in 4 mrem/yr Assumes 2 L/day consumption Assumes 70 kg person

131 MCL – Man-Made Beta and Gamma Emitters
H-3 and Sr-90 MCLs specified in 40 CFR H-3 = 20,000 pCi/L Sr-90 = 8 pCi/L Others are calculated Examples Cesium-137 = 200 pCi/L Iodine-131 = 3 pCi/L Carbon-14 = 2,000 pCi/L

132 Analysis

133 Factors in determining concentration
Count rate Counter Efficiency Geometry Self-absorption Intensity (# of rays per disintegration) Half-life Sample mass

134 Analysis Against MCLs Use radiation emitted to determine the quantity of material. Measure counts per minute or per second Convert to disintegrations per minute (dpm) or disintegrations per second (dps) Counter efficiency Geometry Emissions per disintegration (intensity) Self-absorption Convert to pCi Half-life correction Determine concentration

135 Analysis Against MCLs Radiation emission Rate (gpm) Collection
Activity (pCi) Self- Absorption Sample Size Detector Sensitivity Decay Intensity Geometry Analysis Activity (dpm)  pCi Sample Concentration Count rate found by detector (cpm)

136 Summary Ionization allows detection
Counting technology is determined by properties of radiation MCLs are based on activity concentration Radiochemistry vocabulary and technology are different from chemical methods

137 Radiation Safety John Lorenz Minnesota Department of Health
Public Health Laboratory

138 What we’ll cover Radiation Basics - Review Radiation Health Effects
Radiation Sources in the Lab Protecting Yourself from Radiation Protecting Yourself from Contamination Regulatory requirements

139 What has formed our opinions about radiation?
Chernobyl

140 Basics Of Radiation

141 } } IONIZING vs. NON-IONIZING NON-IONIZING IONIZING LIGHT MICRO- WAVES
HEATING HEAT - } IONIZATION NUCLEAR RADIATION IONIZING +

142 Activity Units Curie (Ci) Becquerels (Bq)
3.7x1010 disintegrations per second Microcuries (mCi) Nanocuries (nCi) Picocuries (pCi) Becquerels (Bq) 1 disintegration per second Megabecquerels

143 MEASURING RADIATION 1 R 1 RAD 1 REM ROENTGEN (R) REM biological dose
the energy of radiation REM biological dose equivalent RAD radiation energy absorbed by any material RADIATION SOURCE 1 R 1 RAD 1 REM

144 AVERAGE ANNUAL EXPOSURE
NATURALLY OCCURRING HUMAN-MADE 70 mREM 300 mREM

145 NATURAL SOURCES TERRESTRIAL COSMIC

146 Human made sources POWER MEDICAL GENERATION CONSUMER PRODUCTS
INDUSTRIAL CONSUMER PRODUCTS POWER GENERATION Human made sources

147 Sources of Radiation – U.S.

148 Exposure limits Radiation Workers 5,000 mrem/yr
General public 100 mrem/yr Declared Pregnant Workers 500 mrem/pregnancy Radiation Workers 5,000 mrem/yr

149 Radiation Health Effects

150 RADIATION EXPOSURE ACUTE DOSE: large dose within
short period 12 1 2 3 4 5 6 7 8 9 10 11 CHRONIC DOSE: small or continuous dose over long period

151 RADIATION EFFECTS SOMATIC EFFECTS: GENETIC EFFECTS:
those effects on the exposed individual GENETIC EFFECTS: those effects on the future generations of the exposed individual

152 RADIATION EFFECTS Cell Death Incomplete Repair Cell Repair

153 RADIATION EFFECTS < 10,000 MREM NO DETECTABLE EFFECTS
50,000 MREM DETECTABLE BLOOD CHANGES 100,000 MREM ONSET OF RADIATION SICKNESS 600,000 MREM FATAL WITH NO MEDICAL ATTENTION

154 LOW LEVEL RADIATION OBSERVABLE EFFECTS NOT IDENTIFIED
EFFECTS MASKED WITHIN OTHER HEALTH EFFECTS KEEP EXPOSURE AS LOW AS REASONABLE

155 Radiation Sources In The Lab

156 Radiation sources in the lab
Assume All the MN Public Health Lab’s radioactive material In your office (1 meter from you) For one working year Your exposure will be less than 50 mrem

157 Protecting Yourself From Radiation

158 EXPOSURE vs. EXPOSURE RATE
EXPOSURE IS THE TOTAL AMOUNT EXPOSURE RATE IS THE AMOUNT PER UNIT TIME 100 mR HR STAYTIME EXPOSURE 1 HOUR 100 mR EXPOSURE R A T E 2 HOURS 200 mR 4 HOURS 400 mR 8 HOURS 800 mR

159 TIME vs. EXPOSURE 100 mR/hr 1 FOOT RADIATION SOURCE 1 HOUR 100 mR
STAYTIME 1 HOUR 100 mR EXPOSURE 2 HOURS 200 mR 4 HOURS 400 mR 8 HOURS 800 mR

160 D E DISTANCE vs. EXPOSURE I R S U T S A O N P RADIATION SOURCE C X
4 mR 5 FEET RADIATION SOURCE 2 FEET 25 mR 1 FOOT 100 mR D I S T A N C E E U R P O S E X

161 SHIELDING vs. EXPOSURE E S H X I E P L O D S I U N R G E

162 Radiation Transmittance
alpha beta gamma Paper Plastic Lead

163 Protecting Yourself From Contamination

164 RADIOLOGICAL CONTAMINATION
RADIOLOGICAL CONTAMINATION IS RADIOACTIVE MATERIAL PRESENT IN AN UNDESIRABLE LOCATION

165 CONTAMINATION NOT SO GOOD RADIOACTIVE LIQUID GOOD

166 WHY IS CONTAMINATION A CONCERN?
Exposure continues until contamination is removed Contamination can spread to other people and objects Contamination can enter the body through ingestion, inhalation, skin absorption, or open wound absorption

167 CONTAMINATION CONTROL
BOUNDARIES PROTECTIVE CLOTHING REMOVAL & SEGREGATION COVERINGS

168 Regulatory Requirements

169 Regulatory Authority Nuclear Regulatory Commission Agreement States
- 10 CFR 19 - 10 CFR 20 - Specific License - General Licenses Agreement States - Comparable State Regulations - State Licenses

170 Required Postings 10 CFR 19.11 or equivalent requires posting of
NRC Form 3 or equivalent 10 CFR 19 and 10 CFR 20 License and License conditions Operating procedures related to licensed activities Violation notices

171 Radioactive Materials
Required Postings Caution Radioactive Materials Required for rooms housing more than: 10,000 mCi H-3; 100 mCi Cs-137; 1 mCi Ra-226 0.001 mCi Am-241

172 Required Postings – Greater Hazards
Caution Radiation Area Caution High Radiation Area Grave Danger Very High Radiation Area

173 Labeling Required for containers holding more than: 1,000 mCi H-3;
Caution Radioactive Materials Cs-137 247 pCi mR/hr 9/18/06 Required for containers holding more than: 1,000 mCi H-3; 10 mCi Cs-137; 0.1 mCi Ra-226 0.001 mCi Am-241 Radioactive Caution Materials Cs-137 247 pCi 9/18/06

174 Radiation Dosimetry Required if more than 10% of exposure limit is likely May be specified in license Worn on trunk of body

175 Radiation Surveys Frequency specified by license Trained personnel
Appropriate instrumentation

176 Other Requirements Training – according to license
Emergency procedures Audits Inventory, receipt and disposal Recordkeeping

177 Summary Everyone is exposed to radiation
Environmental radiochemistry uses low activities Exposures should be kept ALARA Postings and labels indicate where radiological hazards may be present State and federal regulations and licenses define radiation protection requirements


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