bids are invited for title1 - hydrogen fluoride gas detector tubes range 0.17 - 30 ppm , title2 - hydrogen gas detector tubes range 0.05 - 0.8 percent , title3 - nitrogen oxide gas detector tubes range 100 - 2500 ppm , title4 - nitrogen oxide gas detector tubes range 0.5 - 15 ppm , title5 - nitrogen dioxide gas detector tubes range 20 - 1000 ppm , title6 - ammonia gas detector tubes range 50 - 900 ppm , title7 - ammonia gas detector tubes range 1 - 50 ppm , title8 - carbon dioxide gas detector tubes range 1 - 20 percent , title9 - carbon monoxide gas detector tubes range 20 - 1000 ppm , title10 - trichloro ethylene gas detector tubes range 5 - 300 ppm , title11 - sulphur dioxide gas detector tubes range 0.02 - 0.3 percent , title12 - sulphur dioxide gas detector tubes range 0.25 - 10 ppm , title13 - oxygen gas detector tubes range 3 - 24 percent , title14 - nitrogen dioxide gas detector tubes range 0.5 - 30 ppm , title15 - aspirating pump to be used with above detectors total quantity : 119