☢️ Medical Physics & Radiation Dosimetry
Radiation Absorbed Dose (Gray vs Rad) Converter
Convert ionizing radiation energy deposited per unit mass ($D = dE/dm$) between Grays ($\text{Gy}$), Rads ($\text{rd}$), Milligrays ($\text{mGy}$), and $\text{Joules/kg}$.
🦷 Dental X-ray (0.005 mGy)
🏥 CT Scan (7 mGy)
⚠️ ARS Threshold (1 Gy)
🎯 Radiotherapy Fraction (2 Gy)
☠️ LD50 Lethal (5 Gy)
Input Absorbed Dose
Standard Rads (rd)
200.0 rad
Grays (Gy)
2.000 Gy
Centigrays (cGy)
200.0 cGy
Milligrays (mGy)
2,000 mGy
💡 Absorbed Dose Equivalence:
$$1\text{ Gray (Gy)} = 1\text{ J/kg} = 100\text{ Rads (rd)} = 100\text{ cGy} = 1,000\text{ mGy}$$
Understanding Radiation Absorbed Dose ($D$)
Absorbed dose ($D$) measures the physical ionizing radiation energy absorbed per unit mass of matter:
- Definition: $$D = \frac{d\bar{\epsilon}}{dm} \text{ (in Joules/kg = Grays)}$$
- SI Unit (Gray): Named after Louis Harold Gray, $1\text{ Gy} = 1\text{ J/kg}$.
- Historical Rad: $1\text{ Rad} = 100\text{ erg/g} = 0.01\text{ Gy} = 1\text{ cGy}$. In radiation oncology, $1\text{ cGy}$ is frequently used because it equals $1\text{ rad}$.