Convert Roentgens to Microcoulombs per kilogram

Convert Roentgens (R) to Microcoulombs per kilogram (µC/kg) instantly and accurately.

Roentgens (R)
Microcoulombs per kilogram (µC/kg)

Conversion Formula

µC/kg = R × 258

About Roentgens

The roentgen (R) equals exactly 2.58 × 10⁻⁴ C/kg, the historical unit of X-ray and gamma-ray exposure defined in 1928 (ICRU) and redefined exactly in 1962. Still widely used in the US: field survey instruments read in R/h; NRC and EPA regulations cite R and mR; the Chernobyl accounts famously reported readings in R/h. 1 R = 2.58 × 10⁻⁴ C/kg.

About Microcoulombs per kilogram

The microcoulomb per kilogram (µC/kg) equals 10⁻⁶ C/kg ≈ 3.88 mR. Used in precision ionisation chamber measurements for X-ray beam quality characterisation; national standards laboratories express free-air chamber calibration factors in µC/kg. 1 µC/kg = 10⁻⁶ C/kg = 10⁻³ mC/kg.

Quick Reference Table

Roentgens (R)Microcoulombs per kilogram (µC/kg)
1 R258 µC/kg
2 R516 µC/kg
5 R1290 µC/kg
10 R2580 µC/kg
25 R6450 µC/kg
50 R12900 µC/kg
100 R25800 µC/kg

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