The United States Environmental Protection Agency

United States Environmental Protection Agency

The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...

 (EPA) maintains test method

Test method

A test method is a definitive procedure that produces a test result.A test can be considered as technical operation that consists of determination of one or more characteristics of a given product, process or service according to a specified procedure. Often a test is part of an experiment.The test...

s, which are approved procedures for measuring the presence and concentration of physical and chemical pollutants; evaluating properties, such as toxic properties, of chemical substances; or measuring the effects of substances under various conditions. The methods in the Agency index are known as EPA Methods . There are other types of methods such as the ASTM and United States Pharmacopeia

United States Pharmacopeia

The United States Pharmacopeia is the official pharmacopeia of the United States, published dually with the National Formulary as the USP-NF. The United States Pharmacopeial Convention is the nonprofit organization that owns the trademark and copyright to the USP-NF and publishes it every year...

, but the EPA Methods are the most widely accepted and used.

Nomenclature

The method numbers generally range from 1 to 9000 and may have modification letters appended to the end, signifying a newer version of the method has been released. Some ranges of numbers appear to be organized with intention, for example methods 1-99 being air methods or the 7000s being for hazardous waste. Others number ranges, however, seem to only contain random methods, like the 300 and 400 series both being for wet chemistry methods.

Searchable databases

Since the EPA methods are created by different regulatory departments within the EPA, finding methods on the EPA website itself can be challenging. To make finding methods easier, some organizations have created method search databases that organize all the methods into one place and link to actual test methods. Some allow searching by method number, analyte, or other keywords in the method.