Not only was Wednesday Tax Day, it’s also audit season at work. I got a call recently about one of my recurring purchases for nitrogen gas (and the bottle rental), to make sure it’s within the rules. You see, I’m not allowed to buy hazardous materials for the lab with my credit card, with the exception of “commonly available HAZMAT,” which I interpret as anything I can get at the hardware or drug store. Examples of these would be batteries and toner cartridges (two things explicitly listed in the government instruction), partly (mostly?) because they have disposal restrictions.

There was a brief period where the rule was being interpreted as no purchases at all unless you were HAZMAT trained, but we had nobody with a credit card who had such training. There were people who could buy Certaindeath Juice™ if need be, but only if the order had enough zeroes on it — you needed to buy Certaindeath Juice™ in bulk — and our orders didn’t qualify. So I couldn’t buy things that a nine-year-old with a five-dollar bill could get at the grocery store. That Catch-22 eventually got cleared up, but not because anyone understood the phrase “mutually exclusive” or could read a Venn diagram.

So, back to the nitrogen. Is it a hazardous material? I don’t really know for sure. There are HAZMAT rules for sale, use and transport, and I don’t know which ones apply to my situation. You can’t (easily) ship compressed canisters on an airplane — I’ve purchased some things which had to be shipped by ground transport because of this restriction, but once you took care of this, there were no HAZMAT issues. So for nitrogen my gut says no, and more importantly, my lungs say no, based on continual exposure to an 80% mixture for an extended period of time, interrupted briefly by replacement with Helium on a few occasions. I can’t find any official wording that tells me which criteria I should use for HAZMAT purchase restrictions and how to differentiate it from a non-hazardous material, in such a way that you don’t just classify everything as hazardous. That would be the government way, of course. Nitrogen is a simple asphyxiant — it can displace oxygen and you can die. But I can have the same outcome with the plastic bag, so I fear that somebody is going to insist that plastic bags be deemed HAZMAT. Filing cabinets can be made top-heavy and become a danger if they were to fall over and crush you. (Back in my navy days we got periodic safety messages that invariably included a story of someone tipping a vending machine and being crushed. Also the tally of how many things fell off of aircraft). Paper? I can cut myself and bleed to death, or wad it up and choke on it. Is paper HAZMAT? Oh, crud. I hope I don’t give anyone ideas.

The criterion can’t be that there is an MSDS for it, because you can find an MSDS for water. I can’t buy drinking water because of food purchase restrictions, but what if I needed some deionized water for the lab? What are the actual dangers? Hmmm. Prolonged exposure will make you pruny just doesn’t seem to cut it for a hazard. Drinking gallons of the stuff can kill you, but as with the above, examples, that just means that everything is hazardous. At least I have the “commonly available” loophole.

Seems to me that a common-sense approach says no. It doesn’t react with me chemically, it’s not toxic and isn’t a fire hazard. There are safety issues, as with all things; if you try hard enough, anything can be dangerous.