The scientific unit of measurement used to measure the dose received from radiations, such as X-rays or background radiation, is the millisievert (mSv). The table shows the X-ray dose resulting from CT scans of various parts of the body. The table also frequencywavelengthfrequency = wave speed / 1500(3.0*10^8)/1500 = 2*10^5Hz2*10^5can cause burnscan cause skin cancerradiographythe ability to penetrate the skin and tissue but not the bone allowing for an imageof the bones to be createdPage 18 shows the time it would take to get the same dose from background radiation. Part of the body X-ray dose in mSv Time it would take to get the same dose from background radiation Abdomen 9.0 3 years Sinuses 0.5 2 months Spine 4.0 16 months A student suggests that the X-ray dose and the time it would take to get the same dose from background radiation are directly proportional. Use calculations to test this suggestion and state your conclusion.

The unit 'Sievert' is used to measure:Question 52Select one:a.Radiation source strengthb.Radiation dosec.Radioactivityd.Radiation intensity

Choose TRUE if the statement is correct, FALSE if otherwise. Ionization, is the process if a wave has enough energy, that it can remove the inner electrons from atoms. Radiation dose is measured in sieverts (Sv) or millisieverts (mSv). Ionizing waves have a severe effect on living tissue by killing cells or damaging DNA. Ultraviolet (UV) rays, X-rays, and Gamma rays are examples of non-ionizing waves. Radiographers take several X-rays each day and their potential dose is much lower. Some exposure to UV radiation is beneficial like skin uses UV radiation from the Sun to make vitamin D but overexposure is generally harmful. Sun Protection Factor (SPF) is a number used by sunscreen manufacturers to indicate how much longer youcan stay out in the sun before getting burnt.  Microwaves are radio waves with long wavelengths that causes very slightly absorbed by the body and can cause a minor heating effect.

Match each unit used in dosimetry to its definition.Group of answer choicesSI unit of absorbed dose, equal to 1 joule of energy absorbed per kilogram of materialUnit of radiation exposure, equal to the production of 2.58x10-4 coulombs of charge produced by the radiation per kilogram of dry air through which the radiation passesSI unit of activity, equal to one radioactive decay per secondOlder unit of activity, defined to be 3.7x1010 transformations per second, which is approximately the activity of one gram of radiumUnit relating absorbed dose to the degree of biological damage caused by a particular type of radiation

X-rays are used in hospitals for computed tomography (CT) scans. (i) State one other medical use for X-rays. ______________________________________________________________ ______________________________________________________________(1) (ii) State a property of X-rays that makes them suitable for your answer in part (d)(i). ______________________________________________________________ ______________________________________________________________(1)

wall thickening (greater than 2 mm), periappendiceal fatstranding, appendiceal wall thickening, and/or an appendicolith(Fig. 30-1). While there remains a concern of ionizing radia-tion exposure with a CT scan, typical low-dose CT scans resultin exposure of 2 to 4 mSv, which is not significantly higherthan background radiation (3.1 mSv).18 Recent trials have alsosuggested that although low-dose CT scans of 2 mSv do notgenerate high-resolution images, using these lower resolutionimages does not affect clinical outcomes. 19 Intravenous contrastis generally preferred in these studies, but it can be avoided inpatients with allergies or low estimated glomerular filtration rate(less than 30 mL/minute for 1.73 m 2 ). Several meta-analyseshave suggested that CT scan is more sensitive and specific thanultrasound in diagnosing appendicitis.Ultrasound. Ultrasonography has a sensitivity of 0.85 (95%CI 0.79–0.90) and a specificity of 0.90 (95% CI 0.83–0.95).20Graded compression ultrasonography is used to identify theanteroposterior diameter of the appendix. An easily compressibleappendix <5 mm in diameter generally rules out appendicitis.Features on an ultrasound that suggest appendicitis includea diameter of greater than 6 mm, pain with compression,presence of an appendicolith, increased echogenicity of the fat,and periappendiceal fluid. 21 Ultrasound is cheaper and morereadily available than CT scan, and it does not expose patients toionizing radiation, but it is user-dependent and has limited util-ity in obese patients. In addition, graded compression is usually