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PRI Formulas

PRI Summary of Mathematical Application

Calulating mAs mAs = mA x sec
15% Rule to increase density kVp x 1.15
15% Rule to decrease density kVp x .85
15% Rule to maintain density when increasing kVp by 15% mAs/2
15% Rule to maintain density when decreasing kVp by 15% mAs x 2
Inverse Square Law Formula I1/I2 = (D2)^2/(D1)^2
Density Maintenance Formula mAs1/mAs2 = (SID1)^2/(SID2)^2
Inverse square law The intensity of the x-ray beam is inversely proportional to the square of the distance from the source
Created by: dawn2000