Why are gases bombarded by ionizing radiation useful in detection equipment?

Gases bombarded by ionizing radiation are indeed useful in detection equipment primarily because they become conductors of electrical current. When ionizing radiation interacts with the gas, it ionizes some of the gas molecules, creating positive ions and free electrons. This ionization process allows the gas to conduct electricity, enabling the flow of current through the detector.

This characteristic is essential for many types of radiation detection equipment, such as gas-filled detectors (e.g., Geiger-Müller counters or ionization chambers). In these devices, the presence of the ionizing radiation can be quantified by measuring the electrical current produced as a result of ionization.

While it is true that some gases can emit light or change color under specific conditions, these properties are not the primary function that facilitates effective detection of ionizing radiation. Similarly, absorption of radiation is not the main mechanism for detection in this context; rather, it is the ionization and subsequent conductivity that make gas-based detectors important in the field of radiation safety.