Convert Milliroentgens to Roentgens
Convert Milliroentgens (mR) to Roentgens (R) instantly and accurately.
Conversion Formula
R = mR × 0.001
About Milliroentgens
The milliroentgen (mR) equals 2.58 × 10⁻⁷ C/kg. Standard unit in US health physics for area gamma surveys: personal dosimeters and Geiger counters in medical and industrial radiography settings display mR/h; NRC licence conditions often specify dose-rate limits in mR/h at facility boundaries. 1 mR = 2.58 × 10⁻⁷ C/kg.
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
| Milliroentgens (mR) | Roentgens (R) |
|---|---|
| 1 mR | 0.001 R |
| 2 mR | 0.002 R |
| 5 mR | 0.005 R |
| 10 mR | 0.01 R |
| 25 mR | 0.025 R |
| 50 mR | 0.05 R |
| 100 mR | 0.1 R |