Patent ID: 6933733
Filing Date: 2005-08-23
Classification: G01N

Abstract:
1. A chemical concentration measuring system used in a biocontamination deactivation apparatus having a vaporizer that receives a feed stream comprised of a fluid having hydrogen peroxide and at least one chemical component, wherein the chemical concentration measuring system determines the concentration of the hydrogen peroxide in the fluid, the system comprising: sensing means responsive to changes in the concentration of the hydrogen peroxide in the fluid, the sensing means including a capacitive voltage divider circuit including: an alternating current (AC) voltage generator for applying an AC voltage to the capacitive voltage divider circuit; a memory for storing a table of data including capacitance values and corresponding concentration values indicative of the relative concentration of hydrogen peroxide in the fluid; and processing means for measuring a voltage across the second capacitor to determine a capacitance value associated with the first capacitor, and determining the concentration of the hydrogen peroxide in the fluid using the determined capacitance value and the table of data stored in the memory.