The graphic below depicts one possible set-up for analyzing cylinder contents. In this illustration, a normal scuba first-stage regulator connects the cylinder to a fixed-rate flow meter by means of a standard, low-pressure inflation hose. Another common set-up uses the same sort of oxygen regulator as is found in oxygen resuscitation or treatment kits. However, you will have to use special hardware to adapt this regulator for use with standard scuba cylinder valves. The regulator or flow meter connects to the O2 sensor, which in turn connects to the O2 analyzer.