11 Penetration of Ionizing Radiation GAMMA & X-RAYBETAALPHAIn radiation safety, one of the primary concerns is the penetration ability of the radiations involved. As discussed, alpha particles cannot penetrate the dead layer of skin, and are not an external hazard; however, alpha radiation is a very serious internal hazard. Alpha particles are not a concern in radiation safety with XRF devices. Beta radiation is more penetrating than alpha, but less than gamma rays. Gamma radiation is the same as x-ray radiation, with the exception of the fact that it is originated in the nucleus and x-rays originate in the electron cloud surrounding the nucleus. Gamma rays and x-rays are highly penetrating radiations and they are what we must be concerned with in radiation safety for XRF use. Most of the safety concerns have been addressed already by the design of the XRF, which incorporates shielding, collimation, and shutters to minimize exposure from the radioactive sources inside.
12 Radiation Safety RAD = Radiation Absorbed Dose REM = Roentgen Equivalent ManREM = RAD X Factor(Factors X-ray=1, Alpha=20)
13 Roentgen Equivalent Man?? Now that’s a mouthful!
15 Biological Effects of Radiation Most Sensitive - Rapidly dividing cellsBone MarrowLining of digestive tractSome skin cellsLeast SensitiveBoneMuscleNerves
16 Standards & Guidelines Maximum Permissible Limits (MPL’s)National Council on Radiation ProtectionInternational Commission on Radiological ProtectionALARARadiation Doses5 rems per year (whole body)50 rems (extremity or individual organ)0.5 rems during pregnancy
21 A few words about Radiation Safety The Innov-X analyzers does produce radiation and the user should be aware of thisRadiation exposure is negligible with proper use and small with occasional incorrect use
22 A few more words about radiation safety Practice “ALARA.” All radiation exposure should be “As Low As Reasonably Achievable”This means:Do not put fingers, or any other body part in front of the analyzer window.Verify that no one else stands within 3 paces of the analyzer window when instrument is on.Correct operation of instrument involves leaving one hand on handle, and making sure the other hand is away from the window.
23 Safety Factors Time, Distance, Shielding Time - Limit Exposure Dose Distance - Maintain Safe DistanceInverse square lawShielding - High Density Materials
24 Standards & Guidelines Maximum Permissible Limits (MPL’s)National Council on Radiation ProtectionInternational Commission on Radiological ProtectionALARARadiation Doses5 rems per year (whole body)50 rems (extremity or individual organ)0.5 rems during pregnancy
25 Typical Radiation Exposures Airline Attendant 1,000 mR/yrNuclear Power Worker 700 mR/yrGrand Central Station 120 mR/yrMedical Personnel 70 mR/yrLead Inspector 20 mR/yrUniversity Researcher <10 mR/yrChest X-ray mR/each
27 Misuse Example #1Dose to fingers and/or hand in this example is a maximum of 28,000 mrem/hour.Over exposure occurs in 2 hours of window exposure at the hand.
28 Misuse Example #2Dose at exit of sampling window is approximately 28,000 mrem/hr. A 10 second exposure in contact with Torso = 77.8 mremRepeat misuse 64 times/year exceeds 5,000 mrem limit.
29 Safety Features “Deadman” Trigger Software trigger lock Software “proximity sensor”Test Stand
30 Deadman Trigger Trigger must be held for duration of test. Releasing the trigger ends testThis ensure that users intentionally start each testPrevents user from walking away and leaving instrument onIf user picks up analyzer and inadvertently pulls trigger, test will end as soon as trigger is released
31 Deadman TriggerThis feature may be disabled upon customer request AFTER complete radiation safety trainingIt is recommended that this feature is only disabled for companies where only one or two users use the analyzer in a controlled settingDeactivation is NOT recommended in situations where instrument is shared by many users or in spaces occupied by large numbers of people.
32 Trigger Lock User must release software trigger lock before testing Once released, trigger lock remains disabled until 5 minutes elapse after the end of a test
34 “Software Proximity Sensor” Instrument will shut off after 1-2 seconds if sample is not present.Analyzer checks count rate, if count rate is not significantly above air rate, x-rays shut off
35 Test Stand Option Allows for “Hands-Free” Operation of instrument Ideal for turnings and other small parts, Soil Samples, etc.
36 Use Common Sense!Remember, when energized, X-rays come out of the front of the analyzer and act accordingly.Prevent exposure to front of analyzer when instrument is onPay attention to all warning lights on instrument
39 Trigger and Trigger Lock Tests can be started and stopped via either the trigger or the iPAQ.Trigger lock should be put on immediately after pulling trigger to prevent inadvertent start of test.
40 Batteries Charge Batteries completely before use. Only use Innov-X approved chargerInsert batteries in base of unit - Battery is keyed to fix in correct position
41 iPAQ Power Considerations iPAQ is powered by analyzer main battery.iPAQ’s internal processes consume power, even when not in use.A fully charge iPAQ can loose power sitting on a shelf for several weeks – leave iPAQ plugged in when not in use.If iPAQ battery is completely drained, it will not be possible to use iPAQ in analyzer until iPAQ is charged and date is setAny programs added to the main memory will be deleted, but Innov-X program and data are fine.
42 Storage CardAll Innov-X Data and Programs are stored in storage card. They will not be erased even if iPAQ batteryFor proper operation, iPAQ must storage card firmly pushed into the card slot
43 Placing iPAQ in Analyzer iPAQ must be seated properly to communicateBe careful with the connector!Slide iPAQ forward (towards snout) before lifting. Do not angle iPAQ upwards until it is clear of connector
49 Initialization Analyzer electronics “warm up” Detector is cooled to proper temperatureTakes 2 minutes
50 Tap to StandardizeInstrument requires standardization before measurements can be startedPlace standardization mask on front of analyzerTap to Standardize
51 Standardization Standardization checks 316 standard Checks detector resolution and peak positionNeeds to be done when instrument is powered on or after 4 hours of use
52 Standardization finished Instrument displays result of standardization
53 Standardization Failures Make sure battery is completely chargedReset iPAQTurn instrument on and off, remove battery, make sure it is seated correctly
54 Ready to TestTap Start or pull trigger to begin test
55 Test infoClick INFOEnter dataData is stored until changed or erased
56 Test in progress Screen displays elapsed time and “Test in Progress” LED on front of analyzer blinks indicating radiation is being emittedIf view-live updates is on, results will be displayed after minimum time has elapsed
57 Results Display Results displayed—results in %. Error displayed is 1-sigmaPress start or pull trigger to start another test
58 Results OptionsView menu can change the way results appear on the screenResults shows only grade IDChemistry shows all dataTest info shows stored test info
60 Match NumbersWhen determining Grade/Fingerprint Matches, software calculates a “Match Number”This unit-less number is an indication of how good a match is.The lower the number, the betterTypical cutoffs:3 Analytical
61 Software overview Three screens Main—Select program, change password Analytical—Set analysis parametersResults—view all results
62 Searching Libraries Analyzer only searches selected library Make sure library being searched contains grades of interest
63 Check the screenMatch number and selected libraries are shown on screenAnalytical 3Most general search includes all libraries
68 When in doubt, reset!Like all computers, iPAQs can occasionally lock up or “get confused”Two possible resets. Use “soft” reset.Hard reset is only used in extreme circumstances, usually when soft reset doesn’t work.
69 Exit Software!!Software has three layers of menus (Main, Analysis, and results). Must close Main to exit software.Use File-Exit to close
70 Make sure iPAQ is correctly seated iPAQ must be firmly seated in analyzer. Must be attached to connector.iPAQ and storage card must be firmly pressed into the socket.
71 Verify settings If instrument is not matching, verify Correct Library is being searchedMatch number is set correctly3 AnalyticalExact Match is off in Analytical