When using a 50 Ci source of Ir-192 for radiography from 100' away, how many exposures can be made in one hour?

To determine how many exposures can be made in one hour with a 50 Ci source of Ir-192 at a distance of 100 feet, it's essential to consider both the dose rate at that distance and the operational guidelines regarding exposure limits.

Iridium-192 is a commonly used radioactive isotopic source in industrial radiography, primarily due to its suitable half-life and energy characteristics. The activity of the source is given as 50 Ci, and when this source is used for radiography, it must comply with the safety regulations that dictate how long an individual can be exposed to it in a given timeframe.

The dose rate from a 50 Ci Ir-192 source can be calculated based on known decay characteristics and distance, typically measured in millirems per hour or another relevant dosimetry unit. At 100 feet, the dose rate would be significantly reduced due to the inverse square law, which states that the intensity of radiation decreases with the square of the distance from the source.

Radiography procedures generally have strict limits on the permissible dose that a worker can receive in a short period. Assuming a common operational limit, such as a maximum exposure of 100 mrem for example, and knowing the dose rate at 100 feet from the 50