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SimXray randomly produces centimeter measurements of the radiographic projections selected.**

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SimXray generates the centimeter measurements as plus or minus 25% of the average centimeter measurement for the body part.**

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If the PA Projection of the average Chest measures 20 centimeters, SimXray will produce centimeter measurements from 16 centimeters through 24 centimeters.**

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These variations in centimeter thickness of the body part, through which the Central Ray must pass, will change the required technical factors.**

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Example Technical Factors:**

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The Half Value Layer (HVL) for human tissue has been calculated to be 4 centimeters. A 4 centimeter increase in tissue thickness will require a doubling in the beam intensity to produce the same radiographic result as the average centimeter measurement.**

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A 4 centimeter decrease in tissue thickness will require that the beam intensity be halved** to produce the same radiographic result as the average centimeter measurement.

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Each centimeter of tissue thickness will effect the beam intensity +/- 25%.**