Convert Megaroentgens to Roentgens

Convert Megaroentgens (MR) to Roentgens (R) instantly and accurately.

Megaroentgens (MR)
Roentgens (R)

Conversion Formula

R = MR × 1000000

About Megaroentgens

The megaroentgen (MR) equals 258 C/kg. Used only in extreme radiation environments - nuclear detonation effects calculations, prompt gamma pulse environments, and legacy radiation hardness assurance for military electronics specify total ionising exposure in MR(air); calibrated flash X-ray simulators output pulse exposures in MR. 1 MR = 258 C/kg = 10⁶ R.

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.

Quick Reference Table

Megaroentgens (MR)Roentgens (R)
1 MR1000000 R
2 MR2000000 R
5 MR5000000 R
10 MR10000000 R
25 MR25000000 R
50 MR50000000 R
100 MR100000000 R

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