I’m shamefully behind on my blog reading, and therefore didn’t see Richard’s excellent article on lab safety until the Guardian had already closed comments. I’ll therefore have to relate my story as its own post, instead of the comment I’d originally intended.
Richard’s article references a very sad story that’s rather famous among British scientists:
A fair few years ago now, a certain UK Research Council unit installed oxygen sensors in the room where they kept liquid nitrogen tanks. This is because liquid nitrogen rapidly boils at anything approaching room temperature, and naturally the newly gaseous nitrogen will rapidly displace other gasses—including oxygen. So if you’re working with or decanting liquid nitrogen and an oxygen alarm goes off, you get the hell out of Dodge before you asphyxiate. I’ve been there, done that. But in this particular case, the sensors kept going off, making it next to impossible for these particular people to do their work. So they muted the alarm.
Yes, that was a damn fool thing to do, and when there was a leak somebody asphyxiated and they found his body frozen to the floor. But why the sensor kept going off in that situation is something that H&S should have looked at, and, oh I don’t know, made sure the room was adequately ventilated, perhaps? Maybe even moved the tanks someplace else.
This happened while I was doing my PhD in Glasgow, quite close to the facility in question and in an institute funded by the same organisation. Our lab manager therefore took this development extremely seriously, and we were all asked to think of possible solutions to our own liquid nitrogen problem, which was as follows:
We all took it in turns to fill up our lab’s liquid nitrogen containers, and it was a task that everyone dreaded. The tanks were in a deserted corner of the basement, where you would often hear the skitterings of mice behind storage boxes, but never run into a fellow human being. The room was poorly lit, poorly ventilated, and rather musty (don’t worry, they’ve since knocked the old building down and replaced it with a shiny new purpose-built facility). It took ages to fill up the tanks from the single old hose (which would shriek like a banshee as the nitrogen flowed through it, adding to the creepiness of the situation), and your hands would freeze through the thickest of gloves… not to mention the chill that would seep into your feet and then the rest of your body from the fog of nitrogen vapour. Learning that this activity was potentially fatal as well as deeply unpleasant made us dread our turn on the schedule
slightly even more.
The list of suggested remedies was long, technical, and potentially extremely expensive – sensors, lights, alarms, video monitors, new ventilation systems for the whole building, you name it.
Now, there’s an old story that when faced with the problem of normal pens not working in zero gravity, NASA spent years and millions of dollars developing a special pen for astronauts. Meanwhile, Soviet cosmonauts used pencils. This tale has sadly been debunked, but I’m proud to relate that my PhD supervisor is just as ingenious as any mythical Soviet engineer:
“Send people down there in pairs – one to fill the tanks, and the other to watch from the doorway, holding a boat hook to pull them out if they collapse”, he said. “I can provide the boat hook”.
Problem solved! We never needed to use the boat hook, thankfully, but it was nice to know it was there…