Method 202

Determination of Condensible Particulate Matter From Stationary Sources

This method is used for the determination of condensible particulate matter (CPM).  CPM are the substances that pass through the heated filter to condense in the cold components of the sample train.  The filter catch can also be analyzed if required.

Samples are collected isokinetically using a Method 17 sampling train which consists of a probe,  in-stack glass fiber filter and a series of four impingers.  The first three impingers contain 100mL of DI water and the fourth impinger contains 200-300g of silica gel.  After sampling immediately purge the impingers with N2 at 20 L/min. for 1 hour to remove dissolved sulfur dioxide (SO2).  SO2 can convert to SO4 during storage and bias the inorganic CPM value high.  An air purge at 20 L/min. can also be used per the method but the N2 purge is recommended.  The purging procedure is essential when the impinger pH is less than 4.5 indicating the presence of acid gases.  Keep the train on ice during the purge to preserve the moisture catch.

After collection and purging, the contents of the impingers are weighed and measured for moisture determination.  The impinger contents of the three water impingers are combined along with water rinses of each impinger.  Each impinger and the connecting glassware is then rinsed 2 times with methylene chloride.  These rinses are combined in a separate container.  The method does not require cooling the samples for shipment to the laboratory.

A 5mL aliquot is removed from the contents of the water impingers to be used for sulfate analysis by ion chromatography (IC).  The sample is combined, extracted with methylene chloride.  Both the aqueous and organic phases of the extract are taken to dryness to a constant weight.  CPM is equal to the total of both fractions.

Per the method there are some corrections to be made to account for interferences that may be in the sample.  Sulfate is determined by IC and the amount waters of hydration may be subtracted.  Sources that contain ammonia or chloride will form ammonium chloride which would be measured as CPM.  An aliquot of the sample is analyzed for ammonium chloride so that a correction factor can be applied to the final CPM result.

Note that the method also allows for the use of a heated out-of-stack filter as in Method 5 for CPM at sources with high moisture content.  The out-of-stack filter temperature can be adjusted to suit the source conditions.  This train can also be used in conjunction with Method 201 or 201A if the probe is glass-lined.

(EPA 40CFR Part 61 Appendix M)


No Obligation Quotation for Analytical Services

If you would like us to provide a quote for laboratory analysis, just provide us with as much information as you can about your project (the more, the better) and we'll provide you a quote via email. As you are searching or browsing our Analytical Guide, you'll see the Request-A-Quote icon... just click on it to start the request process.

Method Data

Hold Times, Preservatives, Preps, Collection, Analytical & Documentation
Holding Time:   None specified in method.
Preservatives:   None specified in method.
Required Preps:   Glass fiber filter
Collection Method:   Method 17 train following Method 202 and Method 17 procedures.
Analytical Methodology:   Gravimetric and ion chromatography
Documentation:   202

Analyte List*

Analyte Formula CAS Number Detection Limit
Condensible particulate matter

* The analytes and detection limits listed for each method represent the typical detection limits and analytes reported for that particular method. Keep in mind that analyte lists may vary from laboratory to laboratory. Detection limits may also vary from lab to lab and are dependent upon the sample size, matrix, and any interferences that may be present in the sample.