Conventional Testing


Conventional Chemistry

Total Organic Carbon (SM 5310)

This method covers the determination of total organic carbon in surface waters, domestic and industrial wastes.

The sample is homogenized and diluted as necessary and a microportion is injected into a heated reaction chamber packed with an oxidative catalyst such as cobalt oxide, platinum group metals, or barium chromate. The water is vaporized and the organic carbon and inorganic carbon is oxidized to CO2 and H2O. The CO2 is transported in the carrier-gas stream and is measured by means of a nondispersive IR analyzer.

SM 5310B

Tannin and Lignin (SM 5550)

Lignin is a plant constituent that often is discharged as a waste during the manufacture of paper pulp. Another plant constituent, tannin, may enter the water supply through the process of vegetable matter degradation or through the wastes of the tanning industry. Tannin also is applied in the so-called internal treatment of boiler waters, where it reduces scale formation by causing the production of a more easily handled sludge.

SM 5550

Sulfate (EPA 300.0)

The test method covers the determination of common inorganic anions in drinking water, surface water, mixed domestic and industrial wastewaters, groundwater, reagent waters, solids (after extraction), leachates (when no acetic acid is used).


Specific Gravity (ASTM 854)

These test methods cover the determination of the specific gravity of soil solids that pass the 4.75-mm (No. 4) sieve, by means of a water pycnometer. When the soil contains particles larger than the 4.75-mm sieve, Test Method C127 shall be used for the soil solids retained on the 4.75-mm sieve and these test methods shall be used for the soil solids passing the 4.75-mm sieve.
Soil solids for these test methods do not include solids which can be altered by these methods, contaminated with a substance that prohibits the use of these methods, or are highly organic soil solids, such as fibrous matter which floats in water.

ASTM 854

Viscosity (ASTM D445)

This test method specifies a procedure for the determination of the kinematic viscosity, n, of liquid petroleum products, both transparent and opaque, by measuring the time for a volume of liquid to flow under gravity through a calibrated glass capillary viscometer. The dynamic viscosity, h, can be obtained by multiplying the kinematic viscosity, n, by the density, r, of the liquid.


Turbidity (EPA 180.1)

This method is applicable to drinking, surface, and saline waters in the range of turbidity from 0 to 40 nephelometric turbidity units (NTU). Higher values may be obtained with dilution of the sample.


Specific Conductance (EPA 120.1)

This method is applicable to drinking, surface, and saline water, domestic and industrial wastes and acid rain (atmospheric deposition). The specific conductance of a sample is measured by use of a self-contained conductivity meter, Wheatstone bridge-type, or equivalent. Samples are preferable analyzed at 25oC. If not, temperature corrections are made and results reported at 25oC.


Resistivity (ASTM G57-06)

This test method covers the equipment and procedures for the field measurement of soil resistivity, both in situ and for samples removed from the ground, for use in the control of corrosion of buried structures.

ASTM G 57-06

Redox (ASTM D1498)

This practice covers the apparatus and procedure for the electrometric measurement of oxidation-reduction potential (ORP) in water. It does not deal with the manner in which the solutions are prepared, the theoretical interpretation of the oxidation-reduction potential, or the establishment of a standard oxidation-reduction potential for any given system. The practice described has been designed for the routine and process measurement of oxidation-reduction potential.

ASTM D1498

Quaternary Ammonium Compounds (HACH 8337)

The reagents buffer the sample to an acidic pH and include a masking agent to remove potential interferences. The indicator reacts with quaternary ammonium compounds in the sample and forms a pale pink to vivid purple color. This test is applicable to monitor quaternary ammonium compounds in swimming pools and cooling towers. The measurement wavelength is 575 nm.

HACH 8337

Phosphorus (SM 4500/ EPA 365.3)

Phosphorus occurs in natural waters and in wastewaters almost solely as phosphates. These are classified as orthophosphates, condensed phosphates (pyro-, meta-, and other polyphosphates), and organically bound phosphates. They occur in solution, in particles or detritus, or in the bodies of aquatic organisms.

SM 4500 / EPA 365.3

Alkalinity (SM 2320)

Hydroxyl ions present in a sample as a result of dissociation or hydrolysis of solutes react with additions of standard acid. Alkalinity thus depends on the end-point pH used.

SM 2320

Heat of Combustion (ASTM 240/ E711)

Heat of combustion is determined in this test method by burning a weighed sample in an oxygen bomb calorimeter under controlled conditions. The heat of combustion is computed from temperature observations before, during and after combustion with proper allowances for thermochemical and heat transfer corrections. Either isothermal or adiabatic calorimeter jackets can be used.

ASTM D240 / ASTM E711

Conventional Chemistry

Cation Exchange Capacity (EPA 9081)

Method 9081 is applicable to most soils, including calcareous and noncalcareous soils. The method of cation-exchange capacity by summation should be employed for distinctly acid soils.


Chloride (SM 4500/ EPA 300.0)

The chlorination of water supplies and polluted waters serves primarily to destroy or deactivate disease-producing microorganisms. A secondary benefit, particularly in treating drinking water, is the overall improvement in water quality resulting from the reaction of chlorine with ammonia, iron, manganese, sulfide, and some organic substances.

SM 4500 / EPA 300.0

Chlorophyll-a (SM 10200H)

The concentration of photosynthetic pigments is used extensively to estimate phytoplankton biomass. All green plants contain chlorophyll a, which constitutes approximately 1 to 2% of the dry weight of planktonic algae. The important chlorophyll degradation products found in the aquatic environment are the chlorophyllides, pheophorbides, and pheophytins. The presence or absence of the various photosynthetic pigments is used, among other features, to separate the major algal groups.

SM 10200

COD (SM 5220)

COD often is used as a measurement of pollutants in wastewater and natural waters. Chemical oxygen demand (COD) is defined as the amount of a specified oxidant that reacts with the sample under controlled conditions. The quantity of oxidant consumed is expressed in terms of its oxygen equivalence.

SM 5220

Color (SM 2120B)

The platinum-cobalt method is useful for measuring color of potable water and of water in which color is due to naturally occurring materials. It is not applicable to most highly
colored industrial wastewaters.

SM 2120B


Measurement of pH is one of the most important and frequently used tests in water chemistry. Practically every phase of water supply and wastewater treatment (e.g., acid–base neutralization, water softening, precipitation, coagulation, disinfection, and corrosion control) is pH-dependent. pH is used in alkalinity and carbon dioxide measurements and many other acid–base equilibria. At a given temperature the intensity of the acidic or basic character of a solution is indicated by pH or hydrogen ion activity.



Cyanide is highly toxic. Regulations have been established to require the monitoring of cyanide in industrial and domestic wastes and in surface waters. This method is used for determining available cyanide in water and wastewater by ligand exchange, flow injection analysis, and amperometric detection. This method is used in the USEPA’s data gathering and monitoring programs associated with the Clean Water Act, Resource Conservation and Recovery Act, Comprehensive Environmental Response, Compensation and Liability Act, and Safe Drinking Water Act.



The flash point temperature is one measure of the tendency of the test specimen to form a flammable mixture with air under controlled laboratory conditions. It is only one of a number of properties which must be considered in assessing the overall flammability hazard of a material.


Free Liquids/Paint Filter

This method is used to determine the presence of free liquids in a representative sample of waste.

Free Liquids/Paint Filter


The MBAS method has been applied successfully to drinking water samples. In wastewater, industrial wastes, and sludge, numerous materials normally present can interfere seriously if direct determination of MBAS is attempted. Most nonsurfactant aqueous-phase interferences can be removed by sublation.


Oil & Grease (EPA 1664)

This method determines n-hexane extractable material (HEM; oil and grease) and n-hexane extractable material that is not adsorbed by silica gel (SGT-HEM; non-polar material) in surface and saline waters and industrial and domestic aqueous wastes. HEM includes relatively non-volatile hydrocarbons, vegetable oils, animal fats, waxes, soaps, greases, and related materials.


Organic Content

These test methods cover the measurement of moisture content, ash content, and organic matter in peats and other organic soils, such as organic clays, silts, and mucks.

Organic Content

Phenols, Total Recoverable

This method is applicable to the analysis of ground water, drinking, surface, and saline waters, and domestic and industrial wastes. Phenolic materials react with 4-aminoantipyrine in the presence of potassium ferricyanide at a pH of 10 to form a stable reddish-brown antipyrine dye. The amount of color produced is a function of the concentration of phenolic material.


Ion Chromatograph Scan

Part A of the test method covers the determination of common inorganic anions in drinking water, surface water, mixed domestic and industrial wastewaters, groundwater, reagent waters, solids (after extraction), leachates (when no acetic acid is used).

Part B of the test method covers the determination of bromate, chlorate, and chlorite in drinking and reagent waters.

Ion Chromatograph Scan


Accurate determination of fluoride has increased in importance with the growth of the practice of fluoridation of water supplies as a public health measure. Maintenance of an optimal fluoride concentration is essential in maintaining effectiveness and safety of the fluoridation procedure.



Iodide is found in natural waters at concentrations ranging from 40 μg/L in coastal surface seawater to <1 μg/L in deep ocean water and fresh water. Higher concentrations may be found in brines, certain industrial wastes, and waters treated with iodine. Iodide is thermodynamically unstable relative to iodate in oxygenated waters.




Solids, Total

A well-mixed sample is evaporated in a weighed dish and dried to constant weight in an oven at 103 to 105°C. The increase in weight over that of the empty dish represents the total solids. The results may not represent the weight of actual dissolved and suspended solids in wastewater samples.


Solids, Dissolved

A well-mixed sample is filtered through a standard glass fiber filter, and the filtrate is evaporated to dryness in a weighed dish and dried to constant weight at 180°C. The increase in dish weight represents the total dissolved solids. 


Solids, Suspended

A well-mixed sample is filtered through a weighed standard glass-fiber filter and the residue retained on the filter is dried to a constant weight at 103 to 105°C. The increase in weight of the filter represents the total suspended solids.


Solids, Fixed and Volatile

The residue from Method B, C, or D is ignited to constant weight at 550°C. The remaining solids represent the fixed total, dissolved, or suspended solids while the weight lost on ignition is the volatile solids. The determination is useful in control of wastewater treatment plant operation because it offers a rough approximation of the amount of organic matter present in the solid fraction.


Total Settable Solids

This method is for the determination of dissolved hexavalent chromium (as CrO 2-4 ) in ambient waters at EPA water quality criteria (WQC) levels using ion chromatography (IC).