The
measurement of turbidity is currently conducted using a variety of
methodologies for different applications, primarily using calibration standards
composed of formazin, a material which can be difficult to obtain, short-lived,
and toxic. The discrepancies between the various measurement methods lead to
unreliability in sharing meaningful data across applications, and the deficiencies
of the primary calibration standard make it difficult to conduct measurements
in appropriate-technology environments. This research focused on examining the
current methodologies and synthesizing new materials to use as calibration
standards. The selection criteria for these materials were such as to ensure
longevity, stability in solution, and ease of creation. Results showed that
dilutions of dissolved sodium chloride yielded parabolic regression curves of
comparable accuracy to formazin, which could be used for device calibration.
These standards can be easily and safely synthesized in appropriate-technology
settings. The use of fluorescent materials as calibration standards was also
investigated, and the implications of the characteristic curves of turbidity
versus solute concentration are discussed.