supplying and delivery of laboratory chemicals reagents to 19 nos . water testing laboratory for national rural drinking water quality testing monitoring and surveillance programme in state of west bengal under murshidabad division , p . h . e . dte . as-1 chromogenic coliform agar for simulteneous determination & count of escherichia coli and total coliform in water sample as per iso 9308.1:2014 [ merck / himedia ] [ 100 gm. pack ] 2 membrane filter gridded, sterile, individually packed, 47mm dia / 0.45micron porosity. [ 100 nos. pack ] 3 petri dish 75 mm [ 25 nos. × 10 ) pack 4 disodium dihydrogen versenate solution ( 0.01 m ) ( edta ) [ merck ] [ 500 ml. ] 5 hydrochloric acid gr [ merck / thermofischer / sigma / fluka ] [ 500 ml. ] 6 chloroform gr [ merck / thermofischer / sigma / fluka ] [ 500 ml. ] 7 ferrospectral reagent solution , range0.005-5.00 mg / l [ merck ] 4 × 30 ml. a pack 8 tin ( ii ) chloride dihydrate gr [ merck / thermofischer / sigma / fluka ] 100 gm. 9 potassium iodide gr [ merck / thermofischer / sigma / fluka ] [ 100 gm ] 10 silver diethyldithio carbamate gr for analysis of arsenic, 1.01515 [ merck ] [ 5 gm ] 11 zinc filling ( 1-2 width ) for arsenic test [ merck ] [ 500 gm. pack ] 12 lead acetate [ merck ] [ 500 gm. pack ] 13 manganese reagent, range 0.010-10.0 mg / l mn ( 250 test ) [ merck / thermofischer / sigma / fluka ] [ 250 test pack ] 14 acetone [ merck ] [ 500 ml. ]