I have worked in labs for a long time and it is generally a pretty safe work environment despite what some folks imagine. However, occasionally something happens that has the potential to turn pear-shaped.
Today I was making some 5 molar sodium hydroxide solution, which is corrosive. In fact, 1 molar sodium hydroxide is corrosive, 5 molar is five times stronger and so is very corrosive. It was also hot because the solution heats up as the solid dissolves. Without giving it too much thought, I covered the top of the measuring cylinder I was using and inverted it to mix. Unfortunately the combination of heat and alkaline solution dissolved part of the seal on the lid, resulting in a spurt of liquid bursting out and across my bench. Fortunately it went away from my face and didn’t hit anybody else so was mostly just a mess and some on my hand which was easily washed off.
In hindsight there were a few things I did wrong there: Inverting a measuring cylinder is a quick and dirty way to mix solutions but always has the potential for spills – I was taught better than that but have become slack over the years. It also was luck rather than good planning that caused the splash to go away from my face. I was wearing eye protection but probably should also have had a face shield on. Sodium hydroxide in the eyes is one of the worst accidents that can occur in a lab and the only reliable way to avoid it is to have protection between you and the corrosive liquid.
As with most mishaps I’ve had in labs over the years I was not injured, just got a fright. Whether that means I’m a safe worker or just stupid but lucky I’m not sure! It is good though to be reminded of the need to be careful and aware that something could potentially go wrong at any time.