Oxygen portable liquid containers

Dissolved oxygen Winkler reagents Addition of reagent immediately after sampling. Fixed sample should be kept in the dark and analysed as soon as possible. Where measurements are needed on liquids containing high levels of easily oxidisable organic matter, a portable meter should be used, otherwise the copper sul-fate/sulfamic acid mix should be used. DoE recommendation. 

Relatively inexpensive portable colorimetric indicators are now commonly used to detect the presence of a variety of contaminant gases in the atmosphere. These are normally specific for one or perhaps a series of gases. For example, the NBS colorimetric detector uses an indicator tube that contains a 15-mm section of yellow palladous silico-molybdate gel the gel changes color when exposed to carbon monoxide at concentrations as low as 0.001 vol. % in air. Figure 52 shows one version of a commercial unit used for carbon monoxide as well as carbon dioxide, the unsaturated hydrocarbons, and a variety of other gases this unit can also be used to determine the approximate concentrations of contaminants in liquid oxygen. Precise determinations can be made with a variety of analytical tools, including infrared... 

Liquid oxygen is packaged in small portable containers that hold quantities ranging from 1 gal to more than 25 gal (3.8 L to 95 L). These containers, generally termed dewars, are encased in steel shells and are vacuum insulated they maintain the liquid at atmospheric pressure and are consequently not subject to DOT/TC regulations. 

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