Infrared monitor and control for vapor hydrogen peroxide processing techniques

A peroxy vapor system including:

• a treatment region;
• a means for generating peroxy vapor and supplying the peroxy vapor to the treatment region;
• a light source which supplies light to the treatment region with at least a component in the mid-infrared range;
• a detector which individually detects mid-infrared range light that has traversed at least a portion of the first treatment region in (a) a first narrow spectrum absorbed by peroxy vapor, (b) a second narrow spectrum absorbed by a carrier vapor, and (c) a third spectrum absorbed by neither the peroxy vapor nor the carrier vapor;
• a processor for determining at least a concentration of the peroxy vapor from the detected light in the mid-infrared range;
• an integrating means for integrating the determined concentration of peroxy vapor over time;
• and,
• an end of cycle means for terminating generation of the peroxy vapor in accordance with the integrated concentration over time.

A disinfection or sterilization system comprising:

• a treatment chamber;
• a source of aqueous peroxy solution;
• a vaporizer for vaporizing the aqueous peroxy solution to form a peroxy vapor and a water vapor and for supplying the peroxy and water vapors to the treatment chamber;
• a light source which projects a beam of light in a mid-infrared range through the peroxy and water vapors;
• a mid-infrared light detector which detects (a) a first narrow spectrum absorbed by the peroxy vapor and not the water vapor, (b) a second narrow spectrum absorbed by the water vapor and not the peroxy vapor, and (c) a third spectrum absorbed by neither the peroxy nor the water vapor;
• an absorbance/transmittance processor which converts the detected first, second, and third spectrum light into one of (a) absorbance values indicative of mid infrared light absorbed by the peroxy and water vapors and (b) transmittance values indicative of mid-infrared light transmitted through the peroxy and water vapors;
• a processor which converts the determined absorbance/transmittance values into a concentration of the peroxy vapor and a concentration of the water vapor;
• a temperature monitor for monitoring temperature in the treatment chamber;
• a percent saturation processor which converts the concentration of the peroxy vapor, the concentration of the water vapor, and the temperature into an indication of a percent saturation in the treatment chamber;
• and,
• a control processor which controls the generation of peroxy and water vapor in accordance with the determined percent saturation.

A peroxy vapor method including:

• projecting light in a mid-infrared range through a monitored region;
• detecting mid-infrared light in (a) a first narrow spectrum absorbed by the peroxy vapor, (b) a second narrow spectrum absorbed by a carrier vapor, and (c) a third spectrum absorbed by neither the peroxy vapor nor the carrier vapor;
• and,
• determining at least a concentration of the peroxy vapor from the light detected in the mid-infrared range.