Systems, methods, and software that measure a plurality of error values each related to a different condition of an aquatic environment monitoring system including a degradation in a chemical indicator due to photo-aging, a degradation in a chemical indicator due to water-aging, a physical contamination of a chemical indicator, an illumination imbalance related to an optical reader, a degradation of a light source of an optical reader, a contamination in water between an optical reader and a chemical indicator, a displacement due to friction between a chemical indicator apparatus and a monitoring unit, an error intrinsic in a chemical indicator, and an error in distance between a chemical indicator and an optical reader. The plurality of error values are used to determine a confidence level that is compared to a threshold value associated with the monitoring system. A correction instruction is generated for correcting one or more of the conditions.

An embodiment provides a method for deriving an amount of PFAS substances from a total organic fluoride measurement in a sample, including: removing inorganic fluoride from the sample using one or more of an ion exchange cartridge and an exclusion apparatus; preconcentrating, using a solid phase extraction, at least one PFAS substance in the sample; digesting, using a working electrode and a counter electrode, the at least one PFAS substance to an amount of total organic fluoride; and determining, using an analyzer, the amount of total organic fluoride in the sample. Other aspects are described and claimed.

A measuring method of bromate ion concentration includes a first fluorescence intensity measuring process including a process of passing hydrochloric acid through an anion exchanger to elute bromate ions adsorbed to the anion exchanger into the hydrochloric acid and a process of measuring the fluorescence intensity of the hydrochloric acid passed through the anion exchanger, a second fluorescence intensity measuring process including a process of passing a hydrochloric acid solution containing a fluorescent substance whose fluorescence intensity changes due to coexistence of bromate ions through an anion exchanger to elute bromate ions adsorbed to the anion exchanger into the hydrochloric acid solution and a process of measuring the fluorescence intensity of the hydrochloric acid solution passed through the anion exchanger, and a calculation process determining the bromate ion concentration in the water sample by using the difference between the fluorescence intensities of the hydrochloric acid solution and the hydrochloric acid.

A method for detecting and quantifying haloether contamination in aqueous samples. A flow state is artificially induced upon an aqueous sample and a solid phase microextraction (SPME) fiber, upon which an electric potential is applied, is exposed to the flowing aqueous sample in direct immersion mode. Halide ions liberated from electrophoretically dehalogenated haloether compounds contained in the aqueous sample are absorbed upon the SPME fiber, then later desorbed at a gas chromatograph, separated into individual halide ions and analyzed by mass spectrometry. Effects of various parameters such as absorption time, sample pH, salt content, applied voltage, SPME fiber type, flow rate and background matrix are also described.

Multi-parameter water analysis system with a holder removably engageable in an enclosable water chamber having an inlet and outlet in line with plumbing of an aquatic environment and allowing water from the aquatic environment to enter the enclosable water chamber for a chemical indicator of the holder to indicate a physical change via an optical reader, the holder configured to move with respect to the optical reader at least in part due to a motive force provided by the flow of water from the inlet in the enclosable water chamber.

A device for rapid detection of cerebrospinal fluid in a sample fluid, the device uses a sample pad with sensors for detecting the presence of one or more analytes in the sample fluid and an analyzer operatively connected to the sample pad, for quantitative analysis of one or more analytes. A display unit operably connected to the analyzer, for displaying an output of the analysis may also be a part of the device, wherein the display unit may be able to indicate presence or absence of cerebrospinal fluid leakage using an indicator.

A test element (10) used to determine concentration levels of free and total chlorine in a water sample comprises a test pad (12) adhered to a substrate (14), wherein the test pad (12) is impregnated with a stabilized DPD solution. The test pad (12) is color responsive to different concentration levels of chlorine in the water and compared to a color chart to determine the level of free chlorine and/or total chlorine in the water. The stabilized DPD solution may include N,N-diethyl-p-phenylenediamine oxalate salt, a polymeric anhydride such as a methyl-vinyl anhydride and an organo-sulfate such as dimethylsulfone.