Test or investigation results that indicate a particular condition does not exist when it actually does.

Federal Insecticide, Fungicide, and Rodenticide Act.

The measurement of hypochlorous acid (an efficient disinfectant) and hypochlorite ion ( a poor disinfectant) in water. The ratio of these two materials in water is pH dependent. The pH range specified (7.0 to 7.6) ensures that sufficient hypochlorous acid is present to facilitate effective disinfection.

Refers to solid particles generated by condensation of vapors or gases, generally after volatilization from combusted melted substances. Popular usage sometimes loosely includes any type of contaminant.

Any of a group of parasitic lower plants, including molds and mildews, that lack chlorophyll.