Patent ID: 7422909
Filing Date: 2008-09-09
Classification: G01N,Y10T

Abstract:
1. An apparatus for gas sampling from a harsh environment comprising: a sealed housing compactly sized for deployment by suspension within the harsh environment of one of a manhole and wet-well of a sewage collection system; a gas sensor disposed within the housing in selective fluid communication with the environment; a filter disposed within the housing to selectively remove contamination from the housing and prevent saturation of the gas sensor; a pump disposed within the housing to effect selective fluid flow through the gas sensor and filter; and two valves disposed within the housing controlling selective fluid communication with the environment, both valves being three way valves normally closed to the environment, but when energized allow gas to be sampled to flow into the apparatus through an inlet valve and tubing to the gas sensor, then through tubing and an outlet valve back out to the environment while keeping the housing interior otherwise contamination free, and when both valves are not energized the inlet valve is normally open to the contamination free atmosphere of the housing interior and the outlet valve is normally open to the filter such that the gas sensor can be purged of the gas being sampled to return to its baseline, while contamination is removed by being pumped through the filter rendering the complete housing interior contamination free.