A very tragic incident happened last Tuesday night in the Yale machine shop:
At GiantU, my department had our own scare last Friday evening when a very tired graduate student dropped a 1 gallon glass container of benzene, forcing an evacuation of the building and Haz-mat cleaning, keeping students out of the lab for several days until it was safe.
Both of these incidents likely have a common factor: exhaustion.
Graduate students are constantly pushed by their advisors to work more hours, get more data, sleep less. As a computationalist, I may not be likely to spill chemicals, but I do eventually need to drive myself home. And as Mythbusters have shown, driving tired can be just as dangerous as driving drunk. Tired data collection can often be bad data collection, and you may end up doing it all again anyway. If you absolutely must be working, for heavens sake, don't work exhausted and ALONE. Professors, you need sleep too.
Sometimes, everyone needs a reminder that some things are more important than getting one more data point. Sleep is a basic safety precaution.