ASNT Industrial Radiography Radiation Safety Questions, Exams of Health sciences

Download ASNT Industrial Radiography Radiation Safety Questions and more Exams Health sciences in PDF only on Docsity! ASNT Industrial Radiography Radiation Safety Questions In the early years of radiography, what caused personnel to be overexposed? - Poor equipment design, lack of understanding, lack of and poor safety practices. In what year did Marie Curie discover radium? - Late 1898 Who coined the term radioactivity? - Marie and Pierre Curie In the early years of radiography from 1920-1930, the maximum thickness that could be inspected via X-radiation was of steel? - 3" (7.62 cm) Historically, it has been proven that the predominant cause of overexposures is: - 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: - The radiographer Alpha particles were discovered by: - Henri Becquerel The first medical X-ray was conducted at: - Massachusetts General Regulations from one state to the next are essentially the me for radioactive materials - True A radiographer has several avenues to seek guidance and counsel. The first person he or she can turn to is? - their program's radiation safety officer (RSO) The origins of industrial radiography can be attributed to: - Wilhelm Rontgen The two basic types of radiation are: - particulate and electromagnetic Wavelike radiation travels at: - 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: - 186 000 miles/s (299 338 km/s) Matter can be turned into energy. - True Alpha particles are much like a helium nucleus as they have: - two protons, two neutrons and two electrons Beta particles have a/an: - Negative charge Alpha particles have a/an: - Positive charge Beta particles have a mass: - much less than that of an alpha particle In modern radiography the alpha and beta particles are of little concern because: - They travel at sub-light speeds and as such are easily ontained or shielded X-radiation is created by applying a: - high voltage direct current across the cathode of a vacuum tube X-rays are produced by an X-ray tube by the: - passage of electrons across the tube striking the target Radio waves, microwaves and infrared waves are types of: - Nonionizing radiation The neutron has an atomic mass of: - 1 AMU · The shorter the wavelength or higher the frequency, the greater the penetration; as such: - 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 - 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: - "A" number Gamma rays are affected by magnetic fields. - False As a radioisotope decays, the elements return to a stab' state by undergoing several steps; once complete the material continues to produce radiation: - false After 148 days, Ir-192 would have undergone how m half lives? - 2 Activation is the process of bombarding material with: - excess neutrons The total number of _________ identifies an element. - protons Gamma radiation has a shorter wavelength than visible light, therefore making it: - More penetrating 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: - 1 half-value layer The best material to use as shielding would be? - lead When using lead to shield an Ir-192 source, you would need ____________to reduce the original exposure to one-half. - 0.2 in. (5.08 mm) Standing in a 100 mR/h (1000 J-lSv/h) field, the radiographer will make four 10 min exposures. The radiographer's total exposure for the day would be: - 66.7 mR (677 μSv/h) With 30 Ci of iridium with a gamma constant of 5.2 R/h/Ci at 1 ft (52 mSv/h/Ci at 0.3 m), what would your exposure rate be at 1 ft (0.3 m) from the source? - 156 R per hour If you have 73 Ci of Co-60, your exposure rate at 2 ft (0.6 m) from the source would be? - 255.5 R You have an intensity of 50 mR/h at 100 ft (50 μSvv/hat 30.48 m) from the source. Moving to 50 ft (15.24 m) would increase your exposure rate by a factor of what? - 4 times If the radiographer has 100 mR/h at 25ft (1000 μSv at 7.63), the exposure rate at 50 ft (15.24 m) would be ________ with 1 half-value of shielding between the radiographer and the source. - 12.5 mR/h There are __________ type(s) of installation used in radiography - Four (4) The most common type of installation used in field radiography - open How many survey meters are required when conducting radiographic operations? - A sufficient number of calibrated and operable survey meters Radiation survey equipment shall be calibrated _________, and have an overall accuracy of ________ - semiannually; ±20% Which personnel monitoring devices are required prior to performing radiography, excluding permanent installations? - operating rate alarm, survey meter, dosimeter, film badge/TLD What are the three classifications of exposure devices - P - portable; M - mobile; F - fixed Exposure devices are classified by categories I and II per the ANSI standard N432. What are these categories? - Category I: exposes the source through a shutter mechanism or rotation device in which the source never leaves the device; Category II: source is exposed outside the shielded container by mechanical means Caution signs used, unless otherwise authorized by the commission, shall be of a trefoil design using the colors: - a. magenta on a yellow background b. purple on a yellow background c. black on a yellow background d. all of the above Boundary and posting requirements are as follows: - Caution radiation area 5 mR/h (50 mSv/h); caution/danger high radiation area 100 mR/h (1 mSv/h); grave danger, very high radiation area 500 R/h (5 Sv/h) Film badges must be replaced at intervals not to exceed: - one month In the event of an off-scale pocket chamber, an individual's film badge/TLD must be submitted for processing within: - 24 h Dosimetry reports received from the accredited NVLAP personnel dosimeter processor must be maintained by the licensee: - until the commission terminates the license X-radiation is produced when a supply of: - high-speed electrons are introduced from the cathode and strike the anode within a vacuum-sealed envelope Most of the energy used in producing X-rays converts to: - heat In most cases, the standard anode material is: - tungsten Raising the kilovolts on the control panel affects the: - penetrating capabilities of the X-rays produced The structure known as the cathode serves as the _________ source. - electron The high-vacuum envelope is used to reduce: - the problem of electrons colliding with, and being absorbed by, molecules of air Van de Graaff generators obtain their electrons through: - the electrostatic principle The expected penetrating power in steel of 50 kV to 150 kV is: - 1/8 in. to 3/4 in. (3.175 mm to 19.05 mm) In most X-ray tubes what is used as an exit port for the X-radiation energy. - beryllium Increasing ___________ across the filament expends more free electrons, thereby increasing the number of free electrons able to cross and strike the anode target creating more X- radiation - milliamperes The symbol "R" means - Roentgen The acronym rad means: - radiation absorbed dose The roentgen (R) exposure is measured in: - AIR The symbol mR means: - milliroentgen One roentgen or 1R is equal to: - 1000 milliroentgen The acronym rem stands for: - roentgen equivalent man The initialism QF stands for - Quality factor The quality factor for X-rays and gamma rays is: - 1 The quality factor for alpha (ray) particles is - 20 Activity of radioactive material is measured in: - curies Becquerels and curies are units of measurement of: - decay rate Atoms that have excess energy and are unstable are known as: - radioactive Elementary particle units with a negative electrical charge and a mass approximately equal to 1/1840 that of a proton are: - electrons Positively charged elementary particles with a mass approximately equal to 1840 times that of an electron, or 1 AMU, are known as: - protons Unchanged elementary particles with a mass nearly equal to that of a proton are called: - neutrons The area known as the center of an atom is called the: - proton Any byproduct material that is encased in a capsule designed to prevent leakage or escape of the byproduct material is a: - pig A tube through which the radioactive source travels when inside a radiographic exposure device is a/an: - S tube A high radiation area is defined as "an area accessible to individuals, in which they could receive ..." - 100 mR/h (1000 μSv/h) A member of the public or unmonitored individual is allowed to receive up to, but not to exceed: - 2 mR/h, 100 mR/year (20 μSv/h, 1000 μSv/year) When performing radiography in the field, regulations require the radiographer to post with physical barriers or signs the: - high radiation area and radiation area A restricted area is defined as an area: - to which access is restricted for the purpose of controlling radiation exposure A radiographer and assistant are standing in a 2 mR/h (20 μSv/h) field. What would the assistant's total dose be after 4 h? - 8.0 mR (80 μSv) You have 24 exposures to make. Your shot time is 5 min per exposure and you're showing 30 mR/h (300 μSv/h). What will be your total dose at the end of the shift? - 60 mR (600 μSv) A radiographer is receiving 100 mR (1000 μSv) at the crank assembly. The crank assembly is 25 ft (7.62 m) in length. Where would the "RADIATION AREA'' sign be posted? - 111.8 ft (34.08 m) A radiographer is receiving 100 mR/h (1000 μSv/h) at the crank assembly. The crank assembly is 25 ft (7.62 m) in length. How long will it take for the radiographer to receive a total dose of 50 mR (500 11Sv)? - 30 min A non-declared pregnant radiographer or assistant may receive no more than: - 5 R per year (50 mSv) A declared pregnant radiographer or assistant may receive no more than ________ for the entire pregnancy. - 500 mR (5000 μSv) An un-born baby may receive no more than _______ for the entire pregnancy. - 500 mR (5000 11Sv) Your cobalt source of 61 Ci (2257 GBq) is exposed for one single 30-min exposure. This is the only exposure that will be made that day. Assume a 14.0 R (140 mSv) per curie factor, shooting through a 3 half-value collimator. Standing at 100 ft (30.48 m), what will your total exposure be? - 5.3 mR (53 μSv) Assuming you have 88 Ci of lr-192 (3256 GBq), where would you place your high radiation boundary? Assume a R factor of 5.2 R (52 mSv). - 68 ft (20.73 m) A monitored person may receive up to 5000 mR (50 000 μSv) per year. What would be considered an excessive amount of radiation exposure to that individual? - any unnecessary exposure to radiation The primary form of shielding provided by modern exposure devices is: - depleted uranium (DU) A thickness of 0.19 in. (4.83 mm) of lead will reduce the exposure of lr-192 to one-half its original intensity. This is known as the: - half-value layer of lead for the energies associated with Ir-192 Assume that 0.19 in. (4.83 mm) of lead is 1half-value layer. How many half-value layers would you have with a sheet of lead 0.57 in. (14.48 mm) in thickness? - 3 half-value layers Assume 0.19 in. (4.83 mm) of lead is 1 half-value layer, and you have a total of 3 half-value layers of lead between you and 100 mR (1000 μSv), what would your exposure rate be? - 12.5 mR (125 μSv) Assume 0.50 in. (12.7 mm) of steel equals 1 half-value layer for Ir-192. How many half- value layers would you have with 1.5 in. (38.1 mm) of steel? - 3.0 half-value layers Assuming 0.19 in. (4.83 mm) of lead is 1half-value layer, a piece of lead 0.38 in. (9.65 mm) thick would reduce the exposure rate by: - 75% What is the maximum curie strength of a Cobalt-60 source in a type A exposure device? - 10.8 Ci (399.6 GBq) What is the maximum curie strength of an iridium-192 source in a type A exposure device? - 27.0 Ci (999 GBq) A source is being transported with a surface reading of 25 mR and 3 mR at 39.37 in. (250 11Sv and 30 11Sv at 1 m). Which transport label must be used? - Yellow III A White transport label maximum transport index is: - less than 0.5 A Yellow II transport label maximum transport index is: - 1 A Yellow III transport label maximum transport index is: - 5 but less than 10 measured at 39.37 in. (1 m) A shipping container is surveyed and found to be 3 mR/h at 39.37 in. (30 11Sv/h at 1 m). What label would be required? - Yellow III What is the maximum surface reading for a Yellow II labeled container? - 200 mR/h (2000 11Sv/h) What is the maximum surface reading for a Yellow III labeled shipping container? - 200 mR/h (2000 11Sv/h) According to the 49 CFRs, a shipping container labeled as a Yellow II: - must have a surface reading of less than or equal to 50 mR/h (500 11Sv/h) and a transport index of 1 Which government agency regulates transportation of Type A radioactive containers? - DOT What is the maximum surface reading for a source changer? - 200 mR/h (2000 11Sv/h) Exposure devices must be maintained prior to use: - and every three months You have a source of lr-192 with 50 Ci (1850 GBq). The surface reading is 50 mR/h (500 11Sv/h). What would the surface reading be after 150 days? - 12.5 mR/h (125 11Sv/h) Your survey meter has become inoperable. You must: - follow company operating and emergency procedures According to the NRC, who is approved to change out a source? - a trained and qualified person authorized by the licensee Your dosimeter has been discharged beyond its useful range. You must: - follow company operating and emergency procedures Your source has become disconnected. You must: - follow your company's operating and emergency procedures Utilization logs must be kept for: - three years A utilization log must include at a minimum: - make, model and serial number of the exposure device, radiographer's identity and signature, date(s) of use and location(s) Written emergency procedures are in place to handle: - abnormal events in handling and transporting radioactive material What documentation is required to conduct radiography in another state? - "approved" reciprocity, regulations of the host state and radioactive license Fixed facilities, also known as shooting rooms, must be inspected at regular intervals to ensure that all visible and audible warning signals are in place and operable. This is documented : - daily prior to use Licensees must report to the NRC lost, stolen or missing material: - immediately