Sampling devices for detecting particulate contaminants

摘要

Sampling devices for detecting particulate contaminants, particularly radioactive particulate contaminants, in a gaseous medium, such as air. The devices use filters comprising a filter membrane sandwiched between two pieces of plastic material having holes exposing the filter membrane to the gaseous medium. Each filter is moved between a sampling position at which the filter is exposed to the gaseous medium and a measurement position at which the amount of particulate material collected by the filter can be measured. In the measurement position, a gas-tight seal may be formed with the plastic surrounding the filter medium so that the chamber holding the filter may be evacuated for measurement of radioactive particles. The filter may be moved linearly or rotationally. The detector may comprise a detector of radioactive particles.