One of our older sales reps faced this issue many years ago, on a source monitoring job. His instruments were set up in a trailer, ready to demo to a prospective customer. The customer had provided a nice new cylinder labeled “sulfur dioxide in air, 500 ppm.” However, when this gas was applied to an…
Have you ever heard that “The solution to pollution is dilution”? This little aphorism is usually stated as a sort of inside joke, although it is public policy for radon in residences. We saw this principle in action when home builders affected by the Chinese drywall disaster would sometimes open all windows while the homes…
A complete list of nitrogen oxides would include… Nitric oxide, aka nitrogen monoxide (NO), nitrogen(II) oxide Nitrogen dioxide (NO2), nitrogen(IV) oxide Nitrous oxide (N2O), nitrogen(−I,III) oxide Nitrosylazide (N4O), nitrogen(−I,0,I,II) oxide Oxatetrazole (N4O) Dinitrogen trioxide (N2O3), nitrogen(II,IV) oxide Dinitrogen tetroxide (N2O4), nitrogen(IV) oxide Dinitrogen pentoxide (N2O5), nitrogen(V) oxide Trinitramide (N(NO2)3 or N4O6), nitrogen(0,IV) oxides Of primary…
In most cases, the goal is to establish some sort of ventilation control, such that a balance can be achieved between energy conservation and guarding against toxic exposure. Carbon monoxide is usually chosen as the target analyte, unless the vehicular traffic will be largely diesel. While diesel engines do emit CO, it is less than…
In most cases, gas monitoring applications focus on a single gas. There may well be interest in detecting this compound at several points, but the end-user has determined that it has one particular target analyte. Sometimes, though, there will be two gases of interest. Common examples are hydrazine and nitrogen tetroxide; and carbon monoxide and…
The classical first year chemistry definition of “pH” refers back to Danish biochemist Søren Sørenson, who originated the term, alluding to the “potential of hydrogen ion.” Specifically, pH is the negative logarithm of the molar concentration of the hydrogen ion (H+) in the particular solution. This is usually expressed as a formula… pH = -log[H+]…
Interscan started the real analytics movement in the field of gas detection, to demonstrate that at least one company is serious about assuring the best possible analytical accuracy in every measurement our instruments make. After all, the very term “gas detector,” which is far more common than “gas analyzer,” immediately reminds one of detector tubes,…
Sometimes it is necessary to transport sample from some distance to the analyzer. There is no inherent problem in doing this, unless the sample is subject to condensation (see “Sample Conditioning” article); the analyte is unstable; or the interconnect tubing material might exhibit chemisorption properties. Recommended tubing: Bev-A-Line IV (Polyethylene liner with ethyl vinyl acetate…