ASTM_E_3022-2018.pdf

This international standard was developed in accordance with internationally recgnized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.Designation:E3022-18TIONALStandard Practice forMeasurement of Emission Characteristics andRequirements for LED UV-A Lamps Used in FluorescentPenetrant and Magnetic Particle TestingThis standard is issued under the fixed designation E3022;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scoperesponsibility of the user of this standard to establish appro-1.1 This practice covers the procedures for testing thepriate safety,health,and environmental practices and deter-performance of ultraviolet A(UV-A),light emitting diodemine the applicability of regulatory limitations prior to use.(LED)lamps used in fluorescent penetrant and fluorescent1.6 This international standard was developed in accor-magnetic particle testing(see Guides E709 and E2297,anddance with internationally recognized principles on standard-Practices E165/E165M,E1208,E1209,E1210,E1219,E1417/ization established in the Decision on Principles for theE1417M and E1444).2 This specification also includes report-Development of International Standards,Guides and Recom-ing and performance requirements for UV-A LED lamps.mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.1.2 These tests are intended to be performed only by themanufacturer to certify performance of specific lamp models2.Referenced Documents(housing,filter,diodes,electronic circuit design,opticalelements,cooling system,and power supply combination)and2.1 ASTM Standards:3also includes limited acceptance tests for individual lampsE165/E165M Practice for Liquid Penetrant Examination fordelivered to the user.This test procedure is not intended to beGeneral Industryutilized by the end user.E709 Guide for Magnetic Particle TestingE1208 Practice for Fluorescent Liquid Penetrant Testing1.3 This practice is only applicable for UV-A LED lampsUsing the Lipophilic Post-Emulsification Processused in the examination process.This practice is not applicableE1209 Practice for Fluorescent Liquid Penetrant Testingto mercury vapor,gas-discharge,arc or luminescent(fluores-Using the Water-Washable Processcent)lamps or light guides(for example,borescope lightE1210 Practice for Fluorescent Liquid Penetrant Testingsources)Using the Hydrophilic Post-Emulsification Process1.4 The values stated in inch-pound units are to be regardedE1219 Practice for Fluorescent Liquid Penetrant Testingas standard.The values given in parentheses are mathematicalUsing the Solvent-Removable Processconversions to SI units that are provided for information onlyE1316 Terminology for Nondestructive Examinationsand are not considered standard.E1348 Test Method for Transmittance and Color by Spec-1.5 This standard does not purport to address all of thetrophotometry Using Hemispherical Geometrysafety concerns,if any,associated with its use.It is theE1417/E1417M Practice for Liquid Penetrant TestingE1444 Practice for Magnetic Particle TestingE2297 Guide for Use of UV-A and Visible Light Sources andThis test method is under the jurisdiction of ASTM Committee E07 onNondestructive Testing and is the direct responsibility of Subcommittee E07.03 onMeters used in the Liquid Penetrant and Magnetic ParticleLiquid Penetrant and Magnetic Particle Methods.MethodsCurrent edition approved July 1.2018.Published July 2018.Originally approved2.2 Other Standards:in 2015.Last previous edition approved in 2015 as E3022-15.DOI:10.1520/E3022-18ANSI/ISO/IEC 17025 General Requirements for the Com-2 The use of LED lamps for penetrant examination may be covered by a patent.petence of Testing and Calibration LaboratoriesInterested parties are invited to submit information regarding the identification ofalternative(s)to this patented item to ASTM International Headquarters.Yourcomments will receive careful consideration at a meeting of the responsibletechnical committee,which you may attend.3 For referenced ASTM standards,visit the ASTM website,www.astm.org,orNOTE:ASTM International takes no position respecting the validity of any patentcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMrights asserted in connection with any item mentioned in this standard.Users of thisStandards volume information,refer to the standards Document Summary page onstandard are expressly advised that determination of the validity of any such patentthe ASTM website.rights,and the risk of infringement of such rights,are entirely their own4 Available from American National Standards Institute(ANSI),25 W.43rd St.,responsibility.4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM Intemational,100 Barr Harbor Drive,PO Box C700.West Conshohocken.PA 19428-2959.United StatesE3022-18ANSI/NCSL Z540.3 Requirements for the Calibration of3.2.9 transmittance,t-ratio of the radiant flux transmittedMeasuring and Test Equipmentthrough a body to that incident upon it.3.Terminology4.Significance and Use3.1 Definitions-General terms pertaining to ultraviolet A4.1 UV-A lamps are used in fluorescent penetrant and(UV-A)radiation and visible light used in liquid penetrant andmagnetic particle examination processes to excite fluorophoresmagnetic examination are defined in Terminology E1316 and(dyes or pigments)to maximize the contrast and detection ofshall apply to the terms used in this practice.discontinuities.The fluorescent dyes/pigments absorb energyfrom the UV-A radiation and re-emit visible light when3.2 Definitions of Terms Specific to This Standard:reverting to its ground state.This excitation energy conversion3.2.1 battery-powered hand-held lamp,n-lamp poweredallows fluorescence to be observed by the human eye.by a battery used in either stationary or portable applicationswhere line power is not available or convenient.4.2 The emitted spectra of UV-A lamps can greatly affect3.2.1.1 Discussion-These lamps may also have the optionthe efficiency of dye/pigment fluorescent excitation.to be line-powered(that is,alternating current power supply).4.3 Some high-intensity UV-A lamps can produce irradianceSmaller lamps,often referred to as“flashlights”or“torchesTgreater than 10 000 uW/cm2 at 15 in.(381 mm).All high-are used for portable examination of focused zones and oftenintensity UV-A light sources can cause fluorescent dye fadehave a single LEDand increase exposure of the inspectors unprotected eyes andskin to high levels of damaging radiation.3.2.2 current ripple,n-unwanted residual periodic varia-tion(spikes or surges)of the constant current that drives the4.4 UV-A lamps can emit unwanted visible light and harm-LED at a constant power level.ful UV radiation if not properly filtered.Visible light contami-3.2.2.1 Discussion-Ripple is due to incomplete suppres-nation above 400 nm can interfere with the inspection processsion of DC(peak to peak)variance resulting from the powerand must be controlled to minimize reflected glare and maxi-supply,stability of regulation circuitry,circuit design,andmize the contrast of the indication.UV-B and UV-C contami-quality of the electronic components.nation must also be eliminated to prevent exposure to harmfulradiation3.2.3 excitation irradiance,n-irradiance calculated in therange of 347 nm and 382 nm.This corresponds to the range of4.5 Pulse Width Modulation(PWM)and Pulse Firing(PF)wavelengths that effectively excite fluorescent penetrant dyesof UV-A LED circuits are not permitted.(i.e.greater than 80%of relative peak excitation).Nore 1-The ability of existing UV-A radiometers and spectroradiom-3.2.4 irradiance,E,n-radiant flux(power)per unit areaeters to accurately measure the irradiance of pulse width modulated orpulsed fired LEDs and the effect of pulsed firing on indication detectabilityincident on a given surface.Typically measured in units ofis not well understood.micro-watts per square centimeter(uW/cm2).3.2.5 lamp model,n-A lamp with specific design.Any5.Classificationschange to the lamp design requires a change in model5.1 LED UV-A lamps used for nondestructive testing shalldesignation and complete qualification of the new model.be of the following types:3.2.6 light-emitting diode,LED,n-solid state electronic5.1.1 Type A-Line-powered lamps(LED arrays for hand-devices consisting of a semiconductor or semiconductor ele-held and overhead applications)(3.2.5 and 3.2.6).ments that emit radiation or light when powered by a current.5.1.2 Type B-Battery powered hand-held lamps(LED ar-3.2.6.1 Discussion-LEDs emit a relatively narrow band-rays for stationary and portable applications)(3.2.1).width spectrum when a specific current flows through the chip.5.1.3 Type C-Battery powered,handheld lamps(singleLED flashlight or torch for special applications)(3.2.1,Dis-The emitted wavelengths are determined by the semiconductorcussion)material and the doping.The intensity and wavelength canchange depending on the current,age,and chip temperature.6.Apparatus3.2.7 line-powered lamp,n-corded hand-held or overhead6.1 UV-A Radiometer;designed for measuring the irradiancelamps that are line-powered and typically used for stationaryof electromagnetic radiation.UV-A radiometers use a filter andinspections within a controlled production environment.sensor system to produce a bell-shaped(i.e.Gaussian)response3.2.7.1 Discussion-These lamps are used for examinationat 365 nm(3650 A)or top-hat responsivity centered nearof both small and large inspection zones and consist of an LED365 nm(3650 A).365 nm(3650 A)is the peak wavelengtharray.Overhead lamps are used in a stationary inspection boothwhere most penetrant fluorescent dyes exhibit the greatestto flood the inspection area with UV-A radiation.Handheldfluorescence.Ultraviolet radiometers shall be calibrated inlamps are used to flood smaller regions with UV-A radiationaccordance with ANSI/ISO/IEC 17025,ANSI/NCSL Z540.3,and can also be used in portable applications where line poweror equivalent.Radiometers shall be digital and provide ais available.resolution of at least 5 uW/cm2.The sensor front end aperture3.2.8 minimum working distance,n-the distance from thewidth or diameter shall not be greater than 0.5 in.(12.7 mm).inspection surface where the lamp beam profile begins toNorE 2-Photometers or visible light meters are not consideredexhibit non-uniformity.adequate for measuring the visible emission of UV-A lamps whichE3022-18generally have wavelengths in the 400 nm to 450 nm rangebeam in two orthogonal directions to locate the point of6.2 Spectroradiometer,designed to measure the spectralmaximum irradiance.Record the maximum irradiance value.irradiance and absolute irradiance of electromagnetic emission7.4 Beam Irradiance Profile-Affix the UV-A lamp abovesources.Measurement of spectral irradiance requires that suchthe surface of a flat,workbench with the projected beaminstruments be coupled to an integrating sphere or cosineorthogonal to the workbench surface.corrector.This spectroradiometer shall have a resolution of at7.4.1 Type A lamps shall be supplied with alternatingleast 0.5 nm and a minimum signal-to-noise ratio of 50:1.Thecurrent(ac)power supply at the manufacturers rated powersystem shall be capable of measuring absolute spectral irradi-requirement.Power conditioning shall be used to ensure aance over a minimum range of 300 to 400 nm.stable power supply free of voltage spikes,ripples,or surges6.2.1 The system shall be calibrated using emission sourcefrom the power supply network.reference standards.7.4.2 Type B and C lamps shall be powered using a constant6.3 Spectrophotometer,designed to measure transmittancevoltage power direct current(DC)supply that provides con-or color coordinates of transmitting specimens.The systemstant DC power at the rated,fully charged battery voltageshall be able to perform a measurement of regular spectral0.5V.transmittance over a minimum range of 300 to 800 nm.7.4.3 The UV-A lamp shall be turned on and allowed tostabilize for a minimum of 30 min before taking measure-7.Test Requirementsments.7.1 Lamp models used for nondestructive testing(NDT)7.4.4 Place the UV-A radiometer on the workbench.Adjustshall be tested in accordance with the requirements of Table 1.the lamp position such that the face of the lamp is 15.0+7.2 LEDs of UV-A Lamps shall be continuously powered0.25 in.(381 6 mm)from the radiometer sensor.Scan thewith the LED drive current exhibiting minimum ripple(seeradiometer across the projected beam in two orthogonal7.6.5).The projected beam shall also not exhibit any perceiv-directions to locate the point of maximum irradiance.Recordable variability in projected beam intensity(i.e.strobing,this location as the zero point.Using a 0.5-in.(12.7-mm)grid,flicker,etc.)(see 7.4.6).translate the radiometer across the projected beam in 0.5-in.(12.7-mm)increments to generate a two-dimensional(2-D)7.3 Maximum Irradiance-Fixture the UV-A lamp 15+plot of the beam profile(irradiance versus position).Position0.25 in(381 6 mm)above the surface of a flat,levelthe radiometer using either an x-y scanner or by manuallyworkbench with the projected beam orthogonal to the work-scanning.When manually scanning,use a sheet with 0.5-in.bench surface.The lamp face shall be parallel to the bench(1.27-cm)or finer squares and record the irradiance value inwithin+0.25 in.(+6 mm).Ensure that battery-powered lampsthe center of each square.The beam irradiance profile shall(Types B and C)are fully charged.Turn on the lamp and allowextend to the point at which the irradiance drops belowto stabilize for 5 min.Place a UV-A radiometer,conforming to200 uWcm2.6.1,on the workbench.Adjust the lamp position such that the7.4.5 Generate and report the 2-D plot of the beam irradi-filter of the lamp is 15.0 0.25 in.(381+12.7 mm)from theance profile(see Fig.1).Map the range of irradiance from 200radiometer sensor.Scan the radiometer across the projectedto1000W/cm2,1000to5000W/cm2,5000to10000uW/cm2,10 000 uW/cm2.Report the minimum beam diam-TABLE 1 UV-A LED Lamp Test Requirements by Lamp Modeleter at 1000 and 200 uw/cm-.TypeTest RequirementsNorE 3-The defined ranges are minimums.Additional ranges are7.3 Maximum Irradiancepermitted.7.4 Beam Irradiance Profile7.5 Minimum Working Distance7.4.6 During the observations of 7.4.1 through 7.4.5,note7.6 Temperature Stabilityany output power variations indicated by perceived changes in7.6.1 Maximum Housing Temperatureprojected beam intensity,flicker,or strobing.Any variations in7.6.4 Emission Spectrum7.6.4.7 Peak Wavelengthobserved beam intensity,flicker,or strobing are unacceptable.7.6.4.8 Full Width Half Maximum(FWHM)7.5 Minimum Working Distance-Affix the lamp approxi-7.6.4.8 Longest Wavelength at Half Maximum7.6.4.9 Excitation Irradiancemately 36 in.(900 mm)above a flat,level workbench covered7.6.5 Current Ripplewith plain white paper.The projected beam shall be orthogonal7.8 Filter Transmittanceto the covered workbench surface.7.3 Maximum Irradiance7.5.1 Measurements shall be performed in a darkened envi-7.4 Beam Irradiance Profileronment with less than 2 fe(21.5 lux)of ambient light and a7.5 Minimum Working Distance7.6 Temperature Stabilitystable temperature at775F(253C).7.6.1 Maximum Housing Temperature7.5.2 Ensure that battery-powered lamps are fully charged.7.6.4 Emission SpectrumB,CThe UV-A lamp shall be turned on and allowed to stabilize for7.6.4.8 Full Width Half Maximum(FWHM)7.6.4.8 Longest Wavelength at Half Maximuma minimum of 30 min before taking measurements.7.6.4.9 Excitation Irradiance7.5.3 Observe the beam pattern produced on the paper.7.6.5 Current RippleLower the lamp until the beam pattern exhibits visible non-7.7 Typical Battery Discharge Time and Discharge Plot7.8 Filter Transmittanceuniformity or reduction in intensity between the individualbeams generated by each LED element or by irregularities inE3022-18Blue1000-5000 u W/cm2Red5,000-10000uw/cm2White 10 000 u W/cm2出出出出出FIG.1 Example of Beam Irradiance Profilethe lamps optical path(Fig.2).Measure the distance from theUniform Beam3-LED Array-Away from Inspection Surface(Beam Profile may be rectangular,circular or triangular)Non-Uniform Beam3-LED Array-Near Inspection SurfaceArrow indicate regions of reduced irradiation,(a)betweenindividual LED beams and(b)due to individual LED beam profilesFIG.2 Example of Univorm and Non-Uniform Projected Beams for Determining Minimum Working Distance4E3022-18lamp face to workbench surface.Record this measurement asthe measurements every 30 min until the peak wavelengththe minimum working distance.varies by no more than=I nm and the excitation irradiance7.6 Temperature Stability-Emission Spectrum,Excitationdoes not vary more than 5%over three consecutive measure-Irradiance,Current Ripple-Testing shall be performed in twoments.Once stabilized,measure the current ripple(7.6.5).steps,at ambient temperature conditions and at the maximum7.6.4 Emission Spectrum Measurementoperating temperature reported by the manufacturer.7.6.4.1 Measurements shall be performed under dark labo-7.6.1 For ambient temperature testing conducted in 7.6.2ratory conditions with a stable temperature.perform the following measurements:7.6.4.2 A spectroradiometer conforming to 6.2 shall be used(a)Emission spectrum(7.6.4.1 through 7.6.4.8).to collect data.(b)Excitation irradiance(7.6.4.9).(c)Maximum lamp housing temperature,and7.6.4.3 Power conditioning shall be used for both the(d)Current ripple(7.6.5).spectroradiometer and Type A lamps to ensure a stable powerFor elevated temperature tests conducted in 7.6.3 performsupply free from voltage spikes,ripple,or surges from thethe following measurements:power supply network.(a)Emission spectrum(7.6.4.1 through 7.6.4.8),7.6.4.4 Type B and C lamps may be powered using a(b)Excitation irradiance(7.6.4.9),andconstant voltage power DC supply that provides constant DC(c)Current ripple(7.6.5).power at the rated,fully charged battery voltage+0.5 V.7.6.2 Ambient Temperature Test-At lamp switch-on,per-7.6.4.5 Adjust the lamp position such that the filter of theform the measurements defined by 7.6.4.Repeat the measure-lamp is 15.0 0.25 in.(381+6 mm)from the spectroradi-ments every 30 min until the peak wavelength varies by noometer sensor aperture and the beam maximum irradiance ismore than 1 nm and the excitation irradiance does not varycentered on the sensor aperture.more than 5%over three consecutive measurements.Once7.6.4.6 Measure and plot the emission spectrum betweenstabilized,measure the current ripple(7.6.5).300 and 400 nm(minimum range).7.6.3 Elevated Temperature Test-Affix the lamp in anenvironmental chamber.Adjust the lamp and spectroradiom-7.6.4.7 Determine the peak wavelength(i.e.wavelengtheter position such that the filter of the lamp is 15.00.25 in.with maximum spectral irradiance).See Fig.3.(381+6 mm)from the sensor aperture of the spectroradiom-7.6.4.8 Calculate the width of the plotted spectrum at 50%eter.Adjust the lamp position such that the beam is centered onof maximum spectral irradiance.Report this as the full-width-the sensor aperture.If the lamp uses a transformer or otherhalf maximum(FWHM)in nanometers.Also determine thepower supply,those components shall also be placed in thelongest wavelength at 50%of maximum spectral irradianceenvironmental chamber.The change in temperature within the(i.e.half maximum).See Fig.3.chamber shall not affect the accuracy of the measurements.7.6.4.9 Calculate the excitation irradiance in uW/cm-,us-7.6.3.1 Set the chamber temperature to the maximum manu-ing:facturers specified operating temperature of the lamp.At lampswitch on,perform the measurements defined by 7.6.4.RepeatExcitation IrradianceNa)dn(1)7.00E046.00E-045.00E-04(2w/4.00E-0450 of peak spectral irradiande2.00E-041.00E-040.00e+00300310320330340350360370380390400Wavelength(nm)FIG.3 Determination of Peak Wavelength,FWHM,and Longest Wavelength at Half Maximum(HM)5