WEF Discussion Forums : Laboratory Management and Technical Issues : QC standard for TSS

Mon, 20 Aug 2012 18:30:42 GMT

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.

Wed, 22 Aug 2012 12:49:29 GMT

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

Mon, 29 Oct 2012 16:25:10 GMT

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.