In reply to Lewan Mats's message of Fri, 5 Jun 2015 07:03:31 +0000: Hi, [snip] >http://www.solarhydrogentrends.com/SHT_performance%20_test.pdf
This document refers to EPA method 3C. A quick web check yielded this document:- http://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CB4QFjAA&url=http%3A%2F%2Fwww.epa.gov%2Fttnemc01%2Fpromgate%2Fm-03c.pdf&ei=IiNyVZauH-LAmQXegoGQAw&usg=AFQjCNGU__tc3sDUn265svT-vANsi9e0Yw&bvm=bv.95039771,d.dGY&cad=rja from which I quote the following:- "2.1 Range. The range of this method depends upon the concentration of samples. The analytical range of TCD's is generally between approximately 10 ppmv and the upper percent range. 2.2 Sensitivity. The sensitivity limit for a compound is defined as the minimum detectable concentration of that compound, or the concentration that produces a signal-to-noise ratio of three to one. For CO2, CH4, N2, and O2, the sensitivity limit is in the low ppmv range." Note "ppmv", which I assume means parts per million by volume. In short the percentages quoted in the report are volume percentages. When water is perfectly electrolyzed, one usually expects 2/3 of the volume to be Hydrogen (67%), so a figure of 86-97%, while anomalous, is not as extraordinary as it may first appear to be. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
