Convert milligray [mGy] to nanogray [nGy] Online | Free radiation-absorbed-dose Converter

Milligray [mGy]: A Common Unit in Radiation Dosimetry

The milligray (mGy) is a unit of absorbed radiation dose equal to 10⁻³ grays (Gy), or one-thousandth of a gray. It is widely used in medical, environmental, and industrial applications where moderate levels of ionizing radiation are involved. In medical imaging, such as X-rays, CT scans, and fluoroscopy, radiation doses are often measured in milligrays. For example, a typical chest X-ray may deliver a dose of around 0.1 mGy, while a CT scan can range from 2 to 20 mGy depending on the body part and procedure. The mGy is also used in radiation therapy planning to define exposure to surrounding healthy tissues that must be minimized. In environmental and occupational safety, monitoring radiation exposure in milligrays helps ensure that workers and the public remain within safe limits set by regulatory bodies. The unit is practical because it provides a manageable scale between very small doses (like microgray) and larger therapeutic doses (measured in grays). Understanding and using the milligray is essential for balancing diagnostic or industrial effectiveness with radiation protection and patient or worker safety.

Nanogray [nGy]: Measuring Extremely Low Radiation Doses

The nanogray (nGy) is a unit of absorbed radiation dose equal to 10⁻⁹ grays (Gy). Since the gray (Gy) is the SI unit that measures the amount of ionizing radiation absorbed by a substance (typically per kilogram), one nanogray represents one-billionth of a gray. This tiny unit is used in situations where radiation doses are extremely low, such as background environmental radiation, space research, or ultra-sensitive radiation detection studies. For example, scientists may use nanograys to measure the small amounts of cosmic radiation received by satellites or astronauts over long periods, or to study natural background radiation in very low-radiation areas. Although it is too small to be relevant for most medical or industrial applications—where doses are typically measured in milligrays (mGy) or grays (Gy)—the nanogray is valuable in research that focuses on long-term, low-level exposure and its possible biological effects. It allows for precise tracking and modeling of minimal energy deposits in matter. The use of the nanogray highlights the importance of accurate measurement at even the smallest scales when studying radiation’s impact on the environment, health, or sensitive equipment.