The minimum lethal dose to humans for the whole body is how many Gy?

The minimum lethal dose for humans exposed to whole-body radiation is indeed around 2 Gy. This threshold is significant because it marks a critical point at which exposure can lead to severe biological effects, including potentially fatal outcomes. At 2 Gy, the human body experiences enough ionizing radiation to cause profound damage to tissues and organs, significantly overwhelming the body's ability to recover.

This lethal dose is derived from studies observing the effects of acute radiation syndrome and the resultant mortality rates. It emphasizes the risk associated with high levels of radiation exposure, where cellular damage, loss of bone marrow function, and compromised immune response can occur, leading to death. Recognizing this threshold is crucial for both risk assessment and the establishment of safety protocols in environments where radiation exposure is possible.

Understanding the physiological impact of radiation at this level helps in making informed decisions regarding safety measures to protect individuals in medical, industrial, and nuclear settings.