ASNT Industrial Radiography Radiation Safety Questions With Correct Answers

In the early years of radiography, what caused personnel to be overexposed? - Answer Poor equipment design, lack of understanding, lack of and poor safety practices. In what year did Marie Curie discover radium? - Answer Late 1898 Who coined the term radioactivity? - Answer Marie and Pierre Curie In the early years of radiography from , the maximum thickness that could be inspected via X-radiation was of steel? - Answer 3" (7.62 cm) Historically, it has been proven that the predominant cause of overexposures is: - Answer Improper surveys, the source being left in an uncontrolled state, the source not being locked once retracted to the shielded position The responsibility to adhere to the regulations, license conditions and company policies falls to: - Answer The radiographer Alpha particles were discovered by: - Answer Henri Becquerel The first medical X-ray was conducted at: - Answer Massachusetts General Regulations from one state to the next are essentially the me for radioactive materials - Answer True A radiographer has several avenues to seek guidance and counsel. The first person he or she can turn to is? - Answer their program's radiation safety officer (RSO) The origins of industrial radiography can be attributed to: - Answer Wilhelm Rontgen The two basic types of radiation are: - Answer particulate and electromagnetic Wavelike radiation travels at: - Answer at the speed of light without regard to pressure, temperature or magnetic fields Gamma rays travel in a wavelike motion at the speed of light, which is: - Answer 186 000 miles/s (299 338 km/s) Matter can be turned into energy. - Answer True Alpha particles are much like a helium nucleus as they have: - Answer two protons, two neutrons and two electrons Beta particles have a/an: - Answer Negative charge Alpha particles have a/an: - Answer Positive charge Beta particles have a mass: - Answer much less than that of an alpha particle In modern radiography the alpha and beta particles are of little concern because: - Answer They travel at sub-light speeds and as such are easily ontained or shielded X-radiation is created by applying a: - Answer high voltage direct current across the cathode of a vacuum tube X-rays are produced by an X-ray tube by the: - Answer passage of electrons across the tube striking the target Radio waves, microwaves and infrared waves are types of: - Answer Nonionizing radiation The neutron has an atomic mass of: - Answer 1 AMU · The shorter the wavelength or higher the frequency, the greater the penetration; as such: - Answer primary beams have greater penetrability than secondary beams Elementary particles with a unit negative electrical charge and a mass approximately equal to 1/1840 that of - Answer Electrons The atomic weight of an atom is the combination of the total number of protons and neutrons held in the nucleus. This is also known as the: - Answer "A" number Gamma rays are affected by magnetic fields. - Answer False As a radioisotope decays, the elements return to a stab' state by undergoing several steps; once complete the material continues to produce radiation: - Answer false After 148 days, Ir-192 would have undergone how m half lives? - Answer 2 Activation is the process of bombarding material with: - Answer excess neutrons The total number of _________ identifies an element. - Answer protons Gamma radiation has a shorter wavelength than visible light, therefore making it: - Answer More penetrating Overexposures to personnel can result in: - Answer cancer, genetic defects carried into further generations, and death All radiation exposures are equally serious and can result - Answer False Ionizing radiation passes through the entire body; as such, damage can occur to the: - Answer skin, internal organs and muscles Prompt effects of radiation exposure to acute doses include: - Answer blood changes, nausea and fatigue Industrial radiography, being one of the most dangerous jobs in the world, has killed: - Answer only one member of the public is known to have died in the world ALARA means: - Answer As low as reasonably achievable The maximum occupational dose for a minor is: - Answer 10% that of an adult radiographer or 5 mSv or 0.5 rem The alpha particle is: - Answer more damaging than the gamma ray The alpha particle has a quality factor of: - Answer 20 Radiation can be detected by the human senses - Answer False Which of the following detects, measures, or in some way records ionizing radiation? - Answer a. thermoluminescent dosimeter b. film badge c. pocket ion chamber (dosimeter) d. survey meter e. rate alarm Which of the two types of survey meters is considered most appropriate for industrial radiography? - Answer geiger-muller tube The survey meter must be capable of measuring a range of: - Answer 2 mR/h through 1 R/h (20 μSv/h through 10 mSv/h) After a source has been returned to the shielded position a survey meter should show - Answer An increase in exposure rate followed by a decrease to zero A survey meter must be calibrated on each scale (1x, 10x, 100x, etc.) at two points: one-third and two-thirds scale. The accuracy of each reading must be within: - Answer 20% a dosimeter - Answer dose rate A rate alarm meter or alarming rate meter must sound a continuous audible alarm greater than 80 dL (0.3 m) at: - Answer 500 mR/h (5000 μSv/h) Dosimeters and rate alarms must be calibrarated - Answer Every 12 months Film badges and thermoluminescent dosimeters (TLD's) are considered dosimeters in the same manner as the pocket ion chamber. The main difference between a film badge and TLD and ion chamber is the: - Answer Ion chamber is a direct reading instrument and that the TLD/film badges must be processed by a National Voluntary Laboratory Accreditation Program (NVLAP) lab Sources must be leak tested every - Answer six months Exposure devices using depleted uranium (DU) must be leak tested every: - Answer 12 months A leak test would be considered failed should the sample tested return a value greater than: - Answer 0.005 μCi (185 Bq) Should a source or exposure devise return a wipe resulting in more than 0.005 μCi (185 Bq) the licensee must do what? - Answer Immediately remove it from service and have it decontaminated or disposed of Gamma alarms (audible & visible), also known as area alarms, must be tested every - Answer day prior to use There are basically three methods of protection from ionizing radiation What are they? - Answer Dense atomic structures, time and distance To determine the total dose received - Answer Multiply the rate of dose by the total time exposed At a dose rate of 60 mR/h (600 11Sv/h), 1h of exposure would be? - Answer 60 mR (600 11Sv) The specific gamma ray constant for Co-60 can be expressed as: - Answer 14 R/h (140 mSv/h) The specific gamma ray constant for Ir-192 can be expressed as: - Answer 5.3 R/h/Ci at 1 ft (140 mSv/Ci at 1 ft) A specific gamma ray constant can be stated as: - Answer dose rate per curie at a specific distance The inverse square law is written as: - Answer the intensity is indirectly proportional to the distance squared Mathematically, the inverse square law is written as: - Answer I (sub 1) x I (sub 2) = D (sub 2) squared x D (sub 1) squared Shielding can be expressed by the amount of shilding provided, so that the amount of shielding that would reduce the original exposure rate to one-half would be stated as: - Answer 1 half-value layer The best material to use as shielding would be? - Answer lead