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QC standard for TSS
Posted: Monday, August 20, 2012 1:30 PM
Joined: 3/16/2012
Posts: 16

with the new Methods update Rule from May 2012, EPA established 12 QC guildlines for all methods, if they are not specific in the method.


One such method is 2540D, Total Suspended Solids.  I was curious what labs used for thier QC standard for this test.  I make a standard using cellulose to equal 100 mg/L - a lot cheaper than buying commercially prepared standards.

Posted: Wednesday, August 22, 2012 7:49 AM
Joined: 10/5/2009
Posts: 49

We make up a 100 ppm solution of diatomaceous earth, purchased as a reagent from one of the big lab suppliers (VWR, Fisher,...).


Chuck Lytle,

City of Portland, OR

Posted: Monday, October 29, 2012 11:25 AM
Joined: 10/12/2009
Posts: 11

Just to save you some grief, EPA did not mandate the 12 essential elements but relegated them to option 3 if a method lacks QC.  Then to top it off, they limited the whole section to chemcial methods so physical methods such as TSS are not included.
Posted: Tuesday, May 12, 2015 10:25 AM
Joined: 4/1/2010
Posts: 6

We include in-house prepared standard suspension (diatomaceous earth) 30 - 50 mg/l range and run with each batch daily.  We also utilize a commercially obtained quality standard weekly. In addition we include a duplicate and a blank.


Standard Methods SM2000-series methods call for a duplicate every 10 samples and residue(s) dried/weighed to constant weight (i.e. repeat cycles of drying, cooling, and weighing)....


Perhaps this applies to "certified" facilities only. 


However, including some sort of quality control (qc) sample(s) is advisable even for the in-house and process control situations samples.  Passing (data within expected range) of these qc samples will give confidence or meaning to the acquired results. happy