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Laboratory Weather Conditions

It’s hot out there in Boston today – hot the way it gets in Arkansas or Georgia, but not too often up here. I, of course, will be hanging out in air-conditioned labs and offices, with no need to stick my head outside, but even so, this would not be a good day to run a small water-sensitive reaction. And I’ve done lab work under conditions that were a lot more coupled to the weather than this. My post-doc lab in Germany was under the “open the windows if you’re hot” system, like many German buildings, and the breeze would redistribute photocopies of JACS papers off my desk and send them towards the hall. Darmstadt never got to the high 90s Fahrenheit while I was there, fortunately (I heard plenty of complaints about the heat at much lower levels, but then I used to complain about how chilly it could get in July). You did have the humidity to worry about, though, both for sensitive reagents and for things like water dripping down the sides of condensers, etc. (The traditional remedy for that is to tie a paper-towel bandana around the bottom of the thing like a sweatband).

I did, though, experience real heat in the lab a few times in Arkansas. The old chemistry building had had its windows bricked up years before, which meant that if the AC faltered or failed, it got pretty toasty pretty fast on the upper floors. The first summer that I did undergrad research, it failed a couple of times and we (enthusiastic scientists all) kept trying to do lab work as the plastic caps popped off the old Mallinckrodt ether cans. (Slicing the metal alloy off of those to open them for the first time is a bygone experience, for sure). We eventually had to flee to the relatively balmy Arkansas summer outside – at least there was the chance of a breeze out there. I’ve spoken over the years with colleagues from India, though, about their experiences in university labs where if you needed to use diethyl ether, you pretty much had to do it in the middle of the night or wait until the rainy season. So I’m glad to have only worked under those conditions briefly!

The usual way that people measure those conditions is by what solvents are liquids or solids (or trying to become gases!) t-Butanol is a marker for a warm lab; it freezes at about 25.5 C (78 F). Diethyl ether boils at 34.6 C just over 94 F, so if that’s actually starting to go, you’re in a mighty hot room. You don’t hear as much about cold labs, but DMSO freezes at 19C (66F), and I’ve certainly worked in labs where it had solidified. (Sometimes you see labs where the AC is cranked so hard in the summer that the DMSO freezes up, which is impressive). Acetic acid is the next common thing that would go on you; that one freezes at 16.6 C, about 62 F, and I don’t think I’ve ever seen it as a solid on an open shelf, which is good.

Comments are welcome about memorable experiences at both ends of the scale!

51 comments on “Laboratory Weather Conditions”

  1. luysii says:

    Not the labs exactly, but in un-airconditioned Philly in the early 60s, women in labor weren’t considered to be running a fever until their temperature was over 100.5 (they were just equilibrated to ambient conditions). At least the delivery rooms were air-conditioned.

    The only Black in our med school class of 125 was from Nigeria. I once said something to the effect, that at least he was used to the heat and humidity. He said they never got used to it.

  2. steve says:

    I think I posted this once before but it’s worth reposting. The Levy building at Penn where I did some of my research used to have a system where the heat was on all the time and it was just offset by the air conditioner in the summer. Well, one summer the air conditioning broke and together with the building heater on it was impossible to do experiments. We couldn’t even get our agarose to gel in order to run DNA digests. We ended up spending almost a week in the cold room doing our experiments until the AC got fixed. Nowadays I’d just pack up and go to the beach but postdocs didn’t have that luxury.

  3. Isidore says:

    Another measure, not directly of heat but of relative humidity, which is, however, related to hot and humid weather outside even if the lab is air conditioned, is how much water condenses from chilled devices in the lab. I have a nitrogen generator and HPLCs in my lab, all of which end up condensing water, the nitrogen generator by pulling water vapor out of the air in the process of removing it and oxygen to produce nitrogen, and the HPLCs by condensing it on the cold (8 C) surfaces of their cooled autosmaplers. In the summer the reservoirs that collect condensed water need to be emptied every other day, in the winter every couple of weeks or longer. Before having a nitrogen generator I used a liquid nitrogen Dewar for nitrogen gas. The Dewar condensed water vapor on its surface as ice, which when the Dewar was finally empty ended up melting and forming a puddle on the floor. You could tell where the Dewars had been by the popped up vinyl tiles. We used sorbent pads with plastic backing all around the Dewar, referred to as Dewar diapers.

  4. Wei says:

    During hot summer week in a lab in France, we ran out of heptane and hexane and couldn’t get resupplied immediately. For a few days we tried to run silica column with pentane. You could see it evaporate inside the column. Needless to say we didn’t produce much that week.

  5. oldnuke says:

    I remember harvesting marsh grasses on the Mississippi coast in the summer from a boat for our natural products chemist. Once. And only once!

  6. chemystry says:

    Well, I seem to recall that the glacial acetic acid in my secondary school (Liverpool, UK) chemistry lab was frequently, well.. glacial.. during the winter months. A bit of a shock the system during my first summer of lab work in Cambridge UK, in a newly refurbished lab with the windows sealed and no air con added (that was resolved after the first summer!) to see all the ether and DCM bottles pop open!

    1. Mark Thorson says:

      On the bottles of Kodak glacial acetic acid (used for the stop bath in both film and paper processing) there was a warning not to shake them when they were cold because the hard lumps of solidified acetic acid could fracture the glass bottle.

    2. Nick K says:

      The old Chemistry building at Imperial College was infamous for being icy cold in Winter. This was in part due to the fact that half of it had been demolished during a botched rebuilding programme. The chemists were used to handling acetic acid, DMSO, and tert-butanol as solids from October until April. On a number of occasions the benzene froze…

      1. Barton Lab Monkey says:

        As a current PhD student on the top floor of the Imperial old chemistry building I can confirm this. The labs are very open/high ceilings and if the heating fails (happens fairly frequently) it has been into the single figures. Then in summer the whole building becomes like a greenhouse and the labs have no AC so it then goes up into the 30s.
        It’s manageable but there’s an unwritten rule in the lab that all ‘room temperature’ reactions are run at 30 oC regardless.

    3. SSG says:

      Greetings, Scouser, from a Woollyback! Since moving to a much warmer climate (or much colder in winter) in USA, I don’t get the chance to say that very often. (:

      1. Boot says:

        First conference I attended after arriving down-under, the lass I’m talking too says I sound like her dad – he was from Bolton. Clearly we didn’t get off on the right foot 🙂

  7. failwhale says:

    We always knew the cooling system had failed at good ol’ 840 Memorial in Cambridge when the windows from the offices to the lab would fog up completely. Scrawling “HELP” in reverse on the glass became a common occurrence.

  8. b says:

    There are also plenty of reagents that will let you know how humid it is in the lab depending on whether they “smoke” when you open the bottle. POCl3 and TMSBr are good examples. Both are fine below ~70% RH, start to go a little crazy above.

    And then in the winter, your water sensitive reactions run perfectly, as long as you can get that damned fine powder into the flask without it flying everywhere due to static.

  9. PS says:

    Air pollution made my lab life miserable in LA. We were doing two color microarrays where the samples were labeled by Cy3 and Cy5. Cy5 apparently is exquisitely sensitive to ozone. So the Cy5 signal will disappear at varying pace depending on air pollution levels. Experiments would work beautifully if I imaged the arrays late on nights when weather systems coming from the ocean would blow the pollution inland and away from the lab. Thank God illumina sequencing came along.
    The other time I had weather related issues was as undergrad trying to compare DNA activity of protein extracts. We had no air conditioning in the lab, the cold room was out and it was a hot summer. I worked on ice but the volumes were small so the samples will tend to warm up rapidly once I take the tube out of the ice bucket. My experiments showed pretty good correlation between the activity of the extracts and the temperature that day. Beyond that the results were completely useless.

  10. Leprachemist says:

    Irish chemist here. I would have though of DMSO as a greasy solid before i read this article. It’s not unusual for your breath to fog in the labs in the middle of winter.
    I also worked in a place that had an unheated outdoor store room and we would have to bring the plastic jugs of acetic acid in the day before to let them melt.

  11. H says:

    I currently work in a lab with huge windows. As the sun starts shining into the lab at 16:00-ish you know it’s time to pack up things before everything melts. No air conditioning is not fun in summer…

    I really prefer the labs where the temperature is one of the things that encourages you to wear a lab coat. Luckily not that rare in northern Europe.

  12. Mark Thorson says:

    I once attended a meeting at Bell Labs in the same building where the transistor was invented. The meeting was in a room near the central air conditioning plant for the whole building, and there was no way to throttle it down. The air conditioning vents were stuffed with paper plates from previous occupants in a totally futile attempt to block the cold air. Here it was, a hot summer day in July in New Jersey, and we were freezing our asses off in this conference room.

  13. Calvin says:

    Ahhh. I remember the days on my PhD in Oxford (pre nice new shiny building). Our part of the building was built in the 70s but they neglected to put any insulation in the roof or walls. We were on the top floor. 3 sides of it were all glass. And there was no heating or cooling. So in the summer it would get mightily warm like a greenhouse and sure enough all that ether would evaporate. There were certainly times where you’d have to leave the lab or take the risk of opening the windows. Or wear shorts under the labcoat and be very careful not to spill anything on your legs. Popping solvent bottles were all part of the fun. Of course the issue was reversed in the winter. They tried to remedy that by putting in electric heaters, but since there was no free wall space, they put them in the ceiling. The taller members of the labs got nice warm heads but for us shorties fleeces jackets and fingerless gloves were the order of the day. Today, my office is lovely and cool, but I can see the heatwaves outside!

    1. CH says:

      “Or wear shorts under the labcoat and be very careful not to spill anything on your legs.”

      Graduate labs at the University of Pittsburgh (and I’m sure many other places) this was the summer wardrobe.

    2. NPChemist says:

      Shiny new building hasn’t made life all that much better – the heating/cooling systems frequently break under the extraction load and we’re banned from working until it’s fixed.

      1. SSG says:

        Frozen DMSO, frozen t-butanol, and frozen postgrads with hoodies and scarves under lab coats are common in Shiny New Building.

  14. Steve says:

    I started out work on my PhD in a small lab at the end of an old building in Sheffield. The teaching lab between us and the rest of the building wasn’t heated. As a result it wasn’t uncommon, in the winter, for an NMR sample dissolved in DMSO to freeze en route to the NMR room.

    1. Chris says:

      Been exactly there and done exactly that! I also remember struggling to get “room temperature” reactions to work in those labs without additional heating…

  15. Joe Q. says:

    I too have not-so-fond memories of freezing NMR samples in DMSO-d6 — though usually caused by excessively air-conditioned basement NMR labs.

  16. process chemist says:

    Our pilot plant was poorly heated and I was running a process that used undecene. One morning, I came in to put the charging lance into the drum and viola: a waxy solid it was! Couldn’t be pumped with even a diaphragm pump. Half a day later with a drum heater we were back in business.

  17. dearieme says:

    I worked in a lab in Queensland where some of the equipment was set up outdoors for use in the summer. But they didn’t call it “summer” they called it “The Wet”, so joy was not unconfined.

  18. PeptoidChemist says:

    In south Florida, a couple summers ago there was a really strong gas smell in the lab. We were checking all the natural gas taps to make sure they were closed, couldn’t figure it out as the smell got more and more intense…and I’ll always remember the moment I poked my head into the hallway and saw each of the other labs on the floor doing the same thing, which was when we decided to evacuate as it continued to get more and more intense. We were all out in the parking lot sweating our asses off and the fire department came.

    Turned out someone in the inorganic lab on our floor spilled some (no idea how much) tert-butyl thiol in the fume hood. We in the other labs were not aware of this. It was almost 100 degrees outside and humid, and I guess what happened was once it vented it got sucked back in to the AC thru the air handlers. It dissipated after a couple hours, no harm no foul except the delay in the afternoon and milling about in the parking lot on an intense summer day.

  19. biotechtoreador says:

    “Acetic acid is the next common thing that would go on you; that one freezes at 16.6 C, about 62 F, and I don’t think I’ve ever seen it as a solid on an open shelf, which is good.”

    I have seen frozen AcOH on a shelf—old lab in Canada in which the heat wouldn’t be turned on until a certain date, which was inevitably after our first cold snap….I also recall the paper towel scarves in the summer. Maybe three nice weeks/year.

  20. Peter Kenny says:

    I believe that d6-DMSO freezes a couple of degrees above the undeuterated compound. It was something that we noted when considering using d6-DMSO as a solvent from a fragment library that we were putting together.

  21. John Harrold says:

    After grad school I joined the Peace Corps and I was stationed at a university in the South Pacific. There was no air conditioning in the labs and it was pretty humid. One semester I taught a physiology class and instead of ordering those fancy pigs from the catalogs we just bought some baby pigs from a local farmer. The dissections occurred over three weeks and the animals were refrigerated between classes. By the third session things were pretty ripe.

  22. steve says:

    Another story, not so much weather-related but maybe could stretch it to say environment-related. I spent a few months in an embryology lab in Nogent-sur-Marne, outside of Paris. I made a wrong turn and came across a sealed door with a red sign and the word “Interdit” (“Forbidden”) on it. I asked one of the women there (the institute was almost all female) and she said that the wing had been home to an old radium lab. They had moved a gamma counter into there and the background was sky-high. After searching they realized that the entire wing was so contaminated that they had to seal off the whole thing. Interestingly, the previous two lab directors that had worked there both died of leukemia. Makes you wonder what sort of chemicals we work with (and/or release into the environment) routinely nowadays that people will be aghast at 20 years from now.

    1. 3rd Gen says:

      My Mom would tell me stories when she was doing research in Schenectady, NY, in a basement lab, in a professors home using the chimney flue as her hood. Also, the stories of using carbon tetrachloride and benzene to rinse glassware without proper PPE. This was the 70s I think. Nowadays, EHS would be all over me if I was running anything in carbon tet or benzene!

      On a side note, my grandfather gave me some of his patents back in the day on the preparation of sodiumborohydride. There was a letter attached to it, that this information was deemed “top secret” by the US government. A second letter, dated much later, said it was clear to discuss. I found it fascinating to read it, because I take it for granted that this is readily available.

  23. Peter says:

    Did my pipetting in the cold room today

  24. gippgig says:

    Decades ago one day it was really hot in high school chemistry. The teacher commented that one student had asked if the class could do some endothermic reactions. I always thought that was a classic.

  25. DoctorOcto says:

    Wollongong Australia: The air that the fumecupboards removed from the lab was replaced directly, with outside air pumped in through sheet metal ducts exposed to direct sunlight.
    The indoor temperature was actually 2 degrees warmer than the outside air temp, which could often be 30+ oC

    India: A small pilot plant where the ventilation was a small fan. As the air temp was clearly above 37 oC, standing near this fan would actually make you warm up faster. Suffice to say our small group of visitors retreated to the air conditioned offices on a regular basis.

  26. Cymantrene says:

    In the plant, one should be aware of cyclohexane in wintertime. We regularly forget it, not exotic enough to keep in mind it’s properties.
    On the othar hand, in summertime the IBCs of pentane start to have a globular form instead of cubic. An added pleasure that pentane is a subject of an extra tax, due to the fact it can be used in motorvehicles, therefore authorities want to have an exact balance of it down to sub-liter scales…

  27. TWS says:

    Not in a lab, but I’ve seen 2 L bottles of dioxane freeze in the middle of winter in the solvent stores here (Sheffield, northern UK). Since the area wasn’t well insulated, I’m not really that surprised, but it did form some really beautiful, large crystals in the bottles.

  28. Anonymous says:

    During graduate school, we collaborated with a small pharma company. Their compound had just unexpectedly been denied FDA approval, so their financial prospects changed dramatically. On the 3rd day, they had an all-hands meeting where 63% of the company was let go. Fun introduction to Pharma!

    After the layoffs, the company tried to immediately save money. We had to complete our 10-day project, so we were working over the weekends. This was rare for this company. When we came in on Saturday, the weather outside was >95°F, and inside it was over 105°C. They turned off the A/C on Friday night and set it to turn on Sunday night!

    The hundreds of -80°C freezers were beeping due to the high ambient temp and all the water baths and incubators were well above 37°C.

    That was one very, very hot day in the lab. Management was notified that wasn’t an effective way to save money and they were likely ruining a lot of things by letting the temps get so high inside the building over the weekends.

    1. PUI Prof says:

      If your management is like my admin, you were probably thanked for the info, and…nothing changed.

  29. pleasecooldown says:

    In Boston, both today and yesterday when I left the building my glasses fogged over completely. Bring on fall!

  30. J. Peterson says:

    I visited an electronic components factory in southern China last summer. Outside it was sweltering, probably high 90’s and drenching humidity. But the workers in the factory enjoyed pleasant, air-conditioned working conditions as they tended the machines cranking out thousands parts each hour.

    It was only later I realized the A/C was -not- for the worker’s comfort – I’m sure significant variations in temperature and humidity could easily screw up the manufacturing process.

  31. Eugene says:

    One of the big boosts to air conditioning after it was invented was climate control in manufacturing. Some products do not turn out right when the temperature and humidity are to high. Textiles come to mind.

    1. DoctorOcto says:

      My understanding is that manufacturing is WHY air conditioning was invented.

  32. Angry Gecko says:

    One hot summer day while working at Apollo in Chelmsford, we had one of the AC units fail which served all the offices on one side of the hallway. This lasted for almost a week, so we had to make due. Picture one side where the engineers were sweating like pigs in shorts and t-shirts, and the other side with the AC at max. Fans where placed to exchange hot and cold air. It helped, but mostly we created a noticable fog in the hallway.

  33. Chemalot says:

    Both my wife and I were working for a Dublin university startup a few years ago. Due to an excellent holiday in India, we were left without sufficient vacation to take time off between Christmas and New Year. But since all the students were off, the heating got shut down. So we spent three days as the only people in the building, which was a creaky 60s construction with large single-skin windows, some of which wouldn’t close properly and were thus bodged with rubber tubing and part towel. After the first day (which peaked at 6 Celsius despite having all the ovens on and open) we came in with full winter hill gear……

  34. SHK says:

    When I was in one of the Big Pharma, the temperature of office and labs in summer time used to go down so low that we had to get sweaters while working on desk. The temp controller with sensor was on the hallway but it was covered with plastic box which was locked all the time. So sometimes we used to put a piece of dry ice on top of the box to slow down the AC.^^

  35. SuperHydride says:

    I’ve the good fortune to be doing my PhD in a university lab in the UK that has some windows which don’t shut and some that don’t open, no air con. It was built in the 1960s and is south facing. Last summer I managed to get 42 C on my temperature probe and this winter it reached 14 C so we get the “best” of both worlds. I’ve certainly repeated literature procedures at “room temperature” that didn’t work in December until I heated them to ~30 C as the group were publishing from India.

  36. sort_of_knowledgable says:

    We had a reagent from a company in Denver that was inefficiently binding to biotin at our sea level location. The difference was attributed to the difference in oxygen level, but I wonder if the significant factor was atmosphere pressure and we needed to wait for a storm like some horror show mad scientist.

  37. Nobody says:

    I was at U of I in ’92 and ’93 when they redid the air conditioning system. In the summer it would be in the mid-90’s in the lab. In the winter, it must have been around 45 F. The coolest thing about it is that the air conditioning was wood-fired, using a lithium bromide-absorption chiller. I vaguely think that NSF bankrolled it, for both the library and the chemistry building.

  38. Tyler says:

    I once had a half full 4 L bottle of DMSO freeze into one large piece because our labs were kept nice and cool year-round. Unfortunately, it was the only DMSO available so I had to warm it up in an incubator and periodically swirl it around. As my patience wore thin, the swirling turned into shaking and the solid chunk broke a clean hole in the bottom of the bottle. That part of the lab became a slipping hazard for the next 30 minutes.

  39. Boot says:

    Frozen glacial was pretty common in Manchester (Northern England) around the turn of the century. In fact almost anything with a freezing point below 20 is at risk most of the year, and first day back from Christmas break could find water ice in unheated teaching labs.

    In Southern Australia, instruments are a higher priority than students (and clearly higher than staff!!), so being the analytical guy had the advantage of full bore AC even as the rest of the lab started to find their cell cultures slowly cooking.

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