First 10 questions were to be replied wrt procedure given along with Reference data 2 Questions were relating to calculating Equivalent sensitivity using nomograph. In one question figure was shown & thickness of penetrameter was to be selected from given options. In another question using same figure( shown as example in ASME section V: 2004 subsection B article 22, SE-1025 page no. 276 & 277). Method of interpreting nomograph was fully explained in given reference sheets.
A
exposure to density
C
B
KV Sensitivity is increasing from A to C, B to C (Points B & C in graph were not sharp as shown) Specular density is higher than diffuse density Definition of Bremsstrahlung employed to denote X-Ray producing mechanism was given in question. Bremsstrahlung was to be selected from given options. Coherent scattering process where photon energy is not changed. Rayleigh scattering
Density increases from 2 to 3. Transmitted light will reduce by 90%
HVT of steel is 1” if 8” of steel shielding is used for Co-60 source of 64 R will reduce to 0.25 R Shielding questions asking to reduce exposure rate to 1/100th of original 2TVT Step wedge exposure & density table was given. HVT was asked In above question it was asked which given exposure would be higher KV. Shape of H & D curve is affected by Development was most suitable option Definition of cold shut, segregation, hot tear and shrinkage with or without reason was given in four separate questions defects were to be identified. Very fine discontinuities to be examined in RT using magnifying glass of 3-5 X Electron emission RT uses Harder X Rays There were 2 questions for calculating Ug of defect at 2” from top and 1” from top. SOD, source size and plate thickness was given. A contrast
B
C D
Graininess KV is increased from 400 to 500 KV effect on radiograph Motion un-sharpness depend on : slit width and thickness If size of source is increased intensity per curie is not following the law due to self absorption If film is not properly agitated
Streaks
Thickness measurement by gamma ray uses the principle of Attenuation The crystalline structure can be checked by Pin hole method is used to measure
Diffraction method effective X-Ray source size
Lead plate containing pin hole should be at : mid of source and film Pin hole method is used for max KV :
240 KV
In micro radiography it is important to maintain :
smaller source size
Plate type IQIs are used, other most popular type IQI is
wire type
Equivalent sensitivity study guide Level-III Q No. 116 Reticulation caused by Sudden Temp change during processing Metol, hydroquinoneor phenidone are used to : Balance the solution balance the pH Purpose of fixture is to
dissolve the un developed silver
When a film packet is opened from stored condition and allowed to cool in dark room temp. Moisture gets entrapped due to low temp film at dark room temp. In gas chamber detector gas used is:
N2
CO2,
When a film has received radiation when it was packed
NH3 it will become fogged
Aluminum weld of 5” thickness can be radiographed by : 400KV X-ray Which one has lowest energy radiation : Cs Ir-192 ( Energy level of all sources was given in reference data) For Radiography of 10 mm steel which one will be used: GM counter in high energy field can’t read because
