SRM 1632e Trace Elements in Coal (Bituminous) - This Standard Reference Material (SRM) is intended primarily for use in the evaluation of techniques used in the analysis of coals and materials of a similar matrix.

SRM 1633c Trace Elements in Coal Fly Ash - This Standard Reference Material (SRM) is intended for use in the evaluation of analytical methods for the determination of constituent elements in coal fly ash or materials of a similar matrix. SRM 1633c is a bituminous coal fly ash that was sieved through a nominal sieve opening of 74 µm (200 mesh) and then blended to assure homogeneity. A unit of SRM 1633c consists of 75 g of powdered material. This data is public in the Certificate of Analysis for this material.

SRM 1635a Trace Elements in Coal (Subbituminous) - This Standard Reference Material (SRM) is intended primarily for the evaluation of techniques used in the analysis of coals and materials of a similar matrix. A unit of SRM 1635a consists of 50 g of subbituminous coal that was ground to pass a 250 µm (60 mesh) sieve, homogenized, bottled under an argon atmosphere, and sealed in an aluminized bag. This data is public in the Certificate of Analysis for this material.

SRM 1941b Organics in Marine Sediment - This Standard Reference Material (SRM) is marine sediment collected at the mouth of the Baltimore (MD) Harbor. SRM 1941b is intended for use in evaluating analytical methods for the determination of selected polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyl (PCB) congeners, and chlorinated pesticides in marine sediment and similar matrices. Information values are also provided for total organic carbon (TOC), total carbon, hydrogen, and nitrogen.

SRM 1944 New York/New Jersey Waterway Sediment - Standard Reference Material (SRM) 1944 is a mixture of marine sediment collected near urban areas in New York and New Jersey. SRM 1944 is intended for use in evaluating analytical methods for the determination of selected polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, and trace elements in marine sediment and similar matrices.

SRM 1945 Organics in Whale Blubber - This Standard Reference Material (SRM) is a frozen whale blubber homogenate intended for use in evaluating analytical methods for the determination of selected polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, polybrominated diphenyl ether (PBDE) congeners, and toxaphene congeners. SRM 1945 has been reanalyzed, and the current Certificate of Analysis has values assigned for additional PCB congeners and pesticides, as well as values assigned for selected PBDE and toxaphene congeners.

SRM 1946 Lake Superior Fish Tissue - This Standard Reference Material (SRM) is a frozen fish tissue homogenate that was prepared from lake trout (Salvelinus namaycush namaycush) collected near the Apostle Islands in Lake Superior (U.S./Canada), and is intended primarily for use in evaluating analytical methods for the determination of polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, polybrominated diphenyl ether (PBDE) congeners, perfluorooctanesulfonic acid (PFOS), fatty acids (including omega-3 fatty acids), extractable fat, methylmercury, total mercury, proximates , ?-he

SRM 1947 Lake Michigan Fish Tissue - This Standard Reference Material (SRM) is a frozen fish tissue homogenate that was prepared from fish collected from Lake Michigan, and is intended primarily for use in evaluating analytical methods for the determination of selected trace elements, methylmercury, total mercury, polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, polybrominated diphenyl ether (PBDE) congeners, perfluoroalkyl acids (PFAAs), proximates, ?-hexabromocyclododecane (?-HBCD), caloric content, and fatty acids in fish tissue and similar matrices.

SRM 194a Ammonium Dihydrogen Phosphate - This Standard Reference Material (SRM) is a highly purified and homogeneous lot of crystalline ammonium dihydrogen phosphate (NH4H2PO4). It is intended primarily for use as a working standard in the calibration and standardization of procedures employed in the fertilizer industry for the determination of ammoniacal nitrogen and phosphorus. A unit of SRM 194a consists of one bottle containing 90 g of crystalline ammonium dihydrogen phosphate. This data is public in the Certificate of Analysis for this material.

SRM 1950 Metabolites in Frozen Human Plasma - This Standard Reference Material (SRM) is intended primarily for validation of methods for determining metabolites such as fatty acids, electrolytes, vitamins, hormones, and amino acids in human plasma and similar materials. This SRM can also be used for comparison of measurement technologies used in metabolomic studies and for quality assurance when assigning values to in-house reference materials. This SRM is intended to represent "normal" human plasma.