Several sensors and techniques have been established to detect the level of hydrogen sulfide in pipelines, and assist engineers in developing degradation profiles. Optical sensors are least commonly used in wastewater settings. More frequently found in industrial and hydrocarbon settings, these sensors shine a beam of light through a sample of gas onto a photodetector. Logging hydrogen sulfide concentration over an extended period of time can provide a useful way of observing real-world system behavior. Logging devices are battery powered, and there is an inherent tradeoff between battery life and measurement frequency. Various methods of controlling hydrogen sulfide corrosion focus on altering the relationship between oxygen demand, dissolved sulfides, and oxygen in the wastewater flow. The depth of this corrosion product does not necessarily correspond to wall loss in a one-to-one ratio. That is, just because an inch of material crumbles away does not mean that an inch of formerly structural concrete has been lost.