Back in the olden days, when I was a counselor at summer camp, Sea Dog and I used to have a little routine whenever someone did something memorably idiotic. We would excuse ourselves from the mess hall while the tables were being cleared, and return just in time for announcements. We would return dressed in long, white lab coats and carry big butterfly nets. After announcing, in great detail, a description of the idiotic action, Sea Dog and I would ‘capture’ the offending party with our butterfly nets, and usually to the accompaniment of raucous laughter, lead our captive from the mess hall “to the state insane asylum”. Offenses varied from sailing directly into instead of alongside the dock, to getting engaged on the basis of a summer romance, to accidentally dowsing oneself with a bucket of water while trying to set a trap for someone else as a practical joke. No one was safe from us, the men in the white coats.
These ancient memories come to mind because of some public training courses I’ve encountered. While delivering generic “function-specific” training, instructors have been known to utter “flash point” and “Class 3” in the same sentence, and then inform the class that the best way to classify DG is to consult the scientists, their people in the “white lab coats”. Now, as a person with multiple university degrees in science, I have absolutely no interest in demeaning the ‘white lab coats’ folks at all, my kind of people in many ways, but I have found a huge difference between what I learned to earn degrees in chemistry and biochemistry versus what the DG regulations say is necessary to perform an accurate transport classification. Just for grins and giggles, here’s a short quiz (Q & A) for you and your lab coat staff to take regarding some fine points of transport classifications.
Q: Liquids may be regulated as flammable DG based upon how easily they catch fire. How are solids regulated regarding flammability?
A: Flammable solid tests involve starting the material on fire with a flame (or a wire) at 1000oC (1832oF). Classification as DG depends not upon whether it was easy to start the material burning, but upon how fast it burns after having been started aflame. So, in essence we have different definitions of flammability, based upon physical state, neither of which I’ve been able to find in my old physical chemistry textbooks.
Q: While we’re at 3 and 4.1, can you compare and/or contrast the difference between flammable and combustible in relation to the physical state of the material?
A: For liquids, combustibles are harder to light than are flammables, and combustible liquids can be a pain for shipments to or from the USA. For solids, “readily combustible” and flammable mean the exact same thing. See the USA’s 49CFR 173.124(a)(3) for confirmation. So, despite what any dictionary might say, sometimes combustible and flammable are synonyms and other times not.
Q: Staying in Class 3, because all three PG’s are authorized, every liquid that is easily ignited and has no other hazards, is allowed to be described as UN1993, Flammable liquid, n.o.s., so long as a technical name is provided, right?
A: False, false, and false. Transport classifications must involve a Proper Shipping Name (PSN) that is as specific as possible. So, a PG II acetone based nail polish remover would probably be UN1090, Acetone Solution, while a PG III acetone based nail polish remover would probably be UN1224, Ketones, liquid, n.o.s., neither of which are UN1993, and neither of which are covered in any chemistry textbook I’ve ever found.
Q: Which college or university course covers ID8000?
A: Yeah, those nail polish removers, depending upon the quantity shipped in any innermost container, may or may not qualify to be re-classified as ID8000, Consumer Commodity. This question could have stumped any of my professors.
Q: For a gas detector sensor that has a concentrated Hydrochloric Acid solution as its electrolyte, which causes a change in electrical potential in the presence of certain gases, is the best transport classification UN1789, Hydrochloric Acid Solution, or UN2800, Batteries, Wet, Non-spillable?
A: Yes. It’s one of those two. Probably. It’s a matter of interpretation of the ‘specifically listed mixture rule’ whether the usage PSN is more specific than the “solution” PSN, especially since “pure” Hydrochloric Acid is actually a solution itself. Complications include consideration of UN3363, Dangerous Goods in Apparatus/Equipment. They must have covered this on one of those spring days so glorious that I accidentally skipped class.
Q: When a scientist discovers an unlisted hazard for a specifically-listed chemical, what is to be done? For example, when UN1504, Sodium Peroxide, 5.1, PG I, has been proven to also be Class 8 (at probably the PG III level), as it has, what is the transport classification?
A: IATA folks say to just use the DG List entry, while the creators of the UN Recommendations and the 49CFR aren’t so pompous. Maybe, it should be UN1504, Sodium Peroxide, 5.1 (8), I, or maybe it should be UN3085, Oxidizing solid, corrosive, n.o.s. (Sodium Peroxide), 5.1 (8), I, although the former is definitely more specific. But the first page of the UN Recommendations is the form to fill out to inform the Subcommittee of Experts, so that they can evaluate the data and consider updating the DG List! Glorious spring weather or not, I’m sure my professors didn’t insist I know this before allowing me to don my cap and gown.
I could go on, especially since we haven’t touched biological materials, such as 6.2 or GMO’s & GMMO’s yet, but I don’t want to anger my editor. Maybe I should have started this column with “Classification: the Most Under-Trained Function”. Or should that be “…the Most Under-Appreciated Function”? But I didn’t.
I still have my own white lab coat. Have lab coat, will classify.
Written 11/01/2012 for HCB Magazine