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Parameter codes are 5-digit codes used to identify the constituent measured and the units of measure. Some parameter code definitions include information about the methods used to measure the constituent, but this level of information is not currently consistent in the naming system.

There are two types of parameter codes:

Fixed-value codes

The result value is a numeric code that represents a textual meaning. [ Tab-separated -- saved to file || Tab-separated -- display to screen || HTML ]

Numeric codes

The result is a numeric value for chemical, physical, and biological data.

The following table shows an example of several parameter codes and definitions. This table also illustrates how several parameter codes may exist for one type of measurement.

    Parameter Code
    Parameter Definition
    00910 Calcium, water, unfiltered, milligrams per liter as calcium carbonate
    00915 Calcium, water, filtered, milligrams per liter
    00916 Calcium, water, unfiltered, recoverable, milligrams per liter
    91051 Calcium, water, filtered, micrograms per liter


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