Propane for Dummies

Ice on a propane tank

For a couple of decades, educators all across the USA have bemoaned the citizenry's increasing scientific illiteracy. Whether it's a plot by social conservatives to keep people uneducated about evolution, genetics and climate change, or just an outgrowth of the pay disparity between technical jobs and teaching, there's undeniable evidence that the populace is becoming less familiar with basic science at the same time that they're becoming more familiar with the private lives of "celebrities." We see the evidence all the time, especially at websites that allow journalism and English literature majors to answer technical questions... like the time eHow.com allowed political scientist Mark Fitzpatrick to hold forth on "What Causes a Propane Tank to Frost Up?"¹ for Hunker.com, even though he had no earthly idea what the reason might be.

In the real word, a physicist or a chemist – heck, just about anyone who knows that propane is a gaseous hydrocarbon (C₃H₈) commonly used as a fuel source – would discuss the fact that propane tanks contain propane under such high pressure that it's in liquid form. This means that the liquid is, by definition, colder than propane's boiling point of -44°F (-42°C). If nothing else, that should be a powerful clue right there... but not for Mark. He says nothing about condensation, nothing about vapor pressure, nothing about the temperature of liquid propane.

No, Mark begins by blathering about the OPD, which he misdefines as

"...a safety feature [that] minimizes small amounts of propane from trickling out of the tank when the tank is in use..."

That's bogus, by the way: the OPD (overfill prevention device) is a safety device that prevents overfilling of the tank. The device that "minimizes [the] amounts of propane... trickling out of the tank" is called a "regulator." Oddly, Fitzpatrick never uses that word in his post; the dumbass. Mark also babbles on about the Venturi effect, which can cause some ice to form on the regulator under high rates of use -- but that wasn't the question. Besides, he mungs up the explanation, anyway. Fitzpatrick continues to display his total ignorance by "explaining" that there may be "quality concerns," in which he opines that "...the Venturi Effect on a propane tank tends to reduce the quality of the propane gas inside";

although he neither explains how this occurs nor defines this "quality" of propane. We presume he means that as the liquid in the tank cools, the pressure of vaporization decreases -- but that's not "quality"! Mark finishes by telling his readers that

"A matter that may complicate the frosting issue is an overfilled propane tank. When tanks are overfilled, the liquid propane is close to the OPD valve."

This is, of course, utter bull: since an OPD valve is by definition an "Overfill Prevention Device," you're not gonna get overfilling with it in place. Talk about your moronic claims!

A lot of Mark's problems are because his science degree is in political science (duh), but he also depended on fellow liberal arts majors for much of his information; harvesting factoids at random from "Artists Resource for Fire." Had he gotten his information from someplace as prosaic as a propane dealer, he might have been able to answer the question. But he didn't and he couldn't. That's how we here at the Antisocial Network decide someone deserves to be our Dumbass of the Day. If you're keeping track, this is Fitzpatrick's fifth award, in five different categories: he's a renaissance dumbass!

¹ The original has been rewritten for Leaf Group, but can still be accessed using the Wayback machine at archive.org. Its URL was   ehow.com/info_8159958_causes-propane-tank-frost-up.html

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