Federal Radiological Monitoring and Assessment Center - PowerPoint Presentation

1. Federal Radiological Monitoring and Assessment Center Monitoring and Sampling Division TrainingMS-50 Module 2“Technical Field Team Training”November 2020U.S. Department of EnergyNational Nuclear Security AdministrationNevada National Security Site

2. Monitoring EquipmentMonitoring TechniquesContamination ControlMS-50 Module 2 Outline

3. Monitoring Equipment

4. Exposure RateThin NaIGM TubeNaI DetectorIon ChamberMeterPersonal Radiation Detector

5. Contamination Instruments & ProbesAlpha Beta Scintillator ProbeGM Pancake ProbeRemovable ContaminationGM Pancake Probe

6. DetectorsAlpha, beta, and gamma probesExposure/dose rateAlarming dosimetersUsesPersonnel surveysDose measurementContamination controlField Team Instrument Kit

7. First Plane - 12 KitsExtra – 12 KitsCMRT Health Physics Kit

8. Measures gamma ExposureRange: 200 µR to 50 R/hr Low Pressure Ion ChamberAuto-ranging & ZeroLUDLUM 9DP-1 ION CHAMBER

9. Alpha / Beta Scintillation ProbeRange: 0 cpm to 999 kcpm Three modes of OperationRATEMAXCOUNTLUDLUM 3002 with 44-93

10. Measures Beta Gamma ContaminationRange: 0 cpm to 999 kcpm Range (with filter): 0 to 500 mR/hIntegrated CountThree modes of OperationRATEMAXCOUNTLUDLUM 26-1 Frisker

11. Measures Beta Gamma radiationRange: 0 uR/hr to 49.9 mR/hrRange: 0 cpm to 999 kcpm Low-level, wide-energy gamma detectionModes of OperationRATEMAXCOUNTLUDLUM 3001 with 44-2First Plane - 12 KitsExtra – 12 Kits

12. UsesRadioisotope identification Activity quantification Low level detectionDetectorsHigh purity germanium Gamma onlyMechanically cooled detectorrequires 12-24 hours to cool down High-Purity Germanium (in situ) DetectorFirst Plane 2 - Ortec Detective DXExtra – 3 Ortec Detectives

13. True and Accurate Dose MeasurementsAerial Measurement Support:Normalize Aerial data to Dose Measured @ 1 meterTrending changes over timePortableRadiation Monitors – Pressurized Ion Chamber3 GE RSDetect

14. Can characterize the extent of deposition (in low dose rate areas)Can be used as impromptu portal monitorsSearch Instruments

15. Used to detect alpha emitters via gamma radiation. Single channel analyzer count rate meterPreset region of interest for 17 keV or 60 keVDisplay Counts per SecondFIDLER - Field Instrument for Detecting Low Energy Radiation

16. Measure ground contamination for plutonium dispersal from Radioisotope thermoelectric generator (RTG) or nuclear weapons accidentsThin crystal Sodium Iodine (NaI) scintillation detectorsAmericium-241 and Plutonium Low-Energy X- and gamma rays SpecFIDLER – Spectral Field Instrument for Detecting Low Energy Radiation20 - SpecFIDLER

17. FIDLERGood when wetLess sensitivityAwkward to carryBigger Probe More durableCover survey area fasterFIDLER vs. Alpha ProbeAlpha ProbeWater (rain or dew) affects responseBetter sensitivityEasier to carryMore susceptible to contaminating the detector

18. TypesHigh volume air flow Low volume air flowParticulate filtersAC or DC poweredUsesDetect airborne contaminationMonitor re-suspensionPersonnel protectionAir SamplerLow and high volume for measuring airborne contamination

19. First Plane5 - High Volume samplers with 4-inch paper5 - low volume samplers with either 2-inch filter paper alone or charcoal cartridge Extra19 - High Volume samplers with 4-inch paper14- low volume samplers with either 2-inch filter paper alone or charcoal cartridge Air Sample Pump

20. EPD (Electronic Personal Dosimeters)DosimetersPassive DosimetersMIRION DMC 3000First Plane – 50Extra - 69Panasonic UD802First Plane - 250Extra – TLD’s supplied from NNSS

21. ClothingProtective coverallsFull Face RespiratorGlovesBootiesOne time useDisposableUsesPersonnel protectionContamination controlRadiation safety Personal Protective EquipmentUsed to protect personnel from contamination

22. Monitoring Techniques

23. General Cautions and GuidanceDeposition Characterization Survey Planning Survey TypesMonitoring Techniques

24. Do not put yourself in dangerAll monitoring activities should follow As Low As Reasonably Achievable (ALARA)Follow Turn-Back LevelsTry to avoid re-suspending contaminationSurvey Precautions

25. Observe the ambient dose rate using the most sensitive instrument and scale to provide the first radiation measurements:Hold the survey meter inside the vehicle and above the lap Keep vehicle windows closed, vents on re-circulateUpon observing ambient dose rate reach turn-back levels, notify Supervisor of your location and readingDriving Precautions

26. Best to have instruments set up in RadResponder (or other system) BEFORE something occursRecord all required data fields Record the value and units displayed on the instrument (raw data)Have a paper log as a backupData Recording

27. Monitor for everythingAlphaBetaGammaIdentify the isotopic mix of the depositionOnce the radionuclide(s) are identified, adjust techniques or frequencyInitial Monitoring

28. General Cautions and GuidanceDeposition Characterization Survey Planning Survey TypesMonitoring Techniques

29. One major objective of the Monitoring Division is to determine the extent of the contamination and establish area boundaries. What is the extent?How wide is the area? Some basic survey patterns of use:10 Point Monitoring SurveyBoundary Survey (without entry)Transect Surveys Deposition Characterization

30. Standardized methodology for quickly gathering required radiological monitoring information. Identify ground deposition, plume direction, and source term. Identify the extent of boundary of the contaminationCollect exposure rate, contamination readings, and either a soil sample or in-situ measurement. This will help with isotope identification and quantification.Number and spacing between the points depend on: Number of respondersSize of affected area10 Point Monitoring Survey

31. Use model to approximate boundariesPerform a boundary survey: Identify boundaries without entering areaIdentify boundaries by transecting the area. Boundary Surveys

32. Start at low backgroundStop at a predetermined dose rate Retrace routeProceed laterally and repeatNotify base at pre-set levelsBoundary Survey without Entry

33. Use model to approximate the boundariesDecide if transects are worth the doseRisk vs. benefitALARAStart at a low background areaCollect measurements at a set intervalTransect Surveys

34. Collect readings at set intervalsContinue survey until readings return to starting levelsProceed laterally and repeatNotify base at pre-set levelsExample: 10 times background ~(100 μRem/h) or exposure rate increases of 1 mrem/h Observe turn back levelsTransecting the Ground Deposition

35. General Cautions and GuidanceDeposition Characterization Survey Planning Early Phase Survey TypesMonitoring Techniques

36. Early Phase (Duration Hours to Weeks)Focuses on quick results for immediate protective action decisionsWorker protectionPublic shelter / evacuationIntermediate Phase (Duration Weeks to Months)Focuses on Derived Response Levels (DRL)Re-entry decisions Examining crop embargo areasLate Phase (Duration Months to Years)Focuses on environmental / clean-up levels Measurements and samples will focus on supporting these decisionsEvolution of a Response

37. Plume Surveyairborne radioactive materialGround Depositionexposure ratecontaminationPublic Supportinfrastructureevacuation / reentryEarly Phase - Types of Surveys

38. Surveys are used to identify:Inhalation exposure from the plume External exposure from the plume Absorption due to contamination of skin and clothesTypes of surveys:Air SamplesPortable instrument looking at the ratio of: Gamma & beta/gamma andBetween exposure rate (1 meter) and ground (3 cm) measurementsPlume Tracking

39. By comparing readings to the table below determine if the plume is elevated, at ground level or has passed.WO - window open; WC - window closedOpen Window / Closed Window TechniqueIf at waist level:WO WCANDIf at ground level:WO WCThen:Β+ ≈ ANDΒ+ ≈ Plume is elevatedΒ+ > ANDΒ+ > Plume is at ground levelΒ+ ≈ ANDΒ+ > Plume has passed - ground contaminationThis only works for Beta and Gamma measurements

40. Survey area should be:Undisturbed, relatively levelOpen area, away from trees, heavy traffic areas, buildingsIf possible, perform surveys at least 3 meters (10 feet) to the side of the road.Ground Deposition MeasurementsAlpha/beta contamination surveys (taken at ground level)Exposure rate (taken at 1 meter above ground)In situ measurements (taken at 1 meter above ground)

41. Exposure Rate1 meter above ground level and ground levelSurface ContaminationTypically at ground levelAlphaBeta – beta/gammaFixed + RemovableIsotopic Identification – In situGround Deposition Practical

42. Transportation CorridorsSurveys are used to evaluate the contamination levels of a roadLocal governments use this information for evacuation and reentry planningFor covering a large areaUse aerial equipment where availableDrive the roads with a vehicle- mounted systemTransportation Corridors

43. Transportation Corridors

44. Critical or Sensitive FacilitiesHospitalsAreas under shelter ordersTransportation hubsPower PlantsCommunication Switching StationsMobile Phone TowersAgricultural and Livestock CareWater, feeding, evacuationRetrieve personal items of evacuees Habitability, Infrastructure, and Re-Entry

45. Support reentry, cleanup, and mitigation activitiesSupport monitoring and decontamination of emergency workers and equipmentSupport monitoring and decontamination efforts for the populationSupport reentry effortsTemporary entry into a restricted zone under controlled conditionsInfrastructure and Re-Entry

46. Contamination Control

47. Keep inside of vehicle as clean as possibleUse plastic to cover inside of vehicle before deploymentChange PPE oftenPut on clean gloves and shoe covers each time you enter the vehicleSurvey personnel before entering the vehicle Contamination Control

48. Perform personnel and equipment monitoring (contamination check) at beginning and end of shiftSurvey vehicle periodically while in the field, document the reading, time, and locationContamination Control

49. Questions?