EPA Method 502/524 Surrogate Standard #1 Back Catalog number: 30070 Manufacturer: ABSOLUTE STANDARDS Availability: In the manufacturer's stock Price on request - + Recommended 684904 N,N-Dimethylvaleramide, 250mg Price on request 679848 Triphenyl phosphate, 100 µg/ml, Methanol, 1ml Price on request 676261 2-Amino-4,8-naphthalenedisulfonic acid, 100mg Price on request