Children mixing citric acid and bicarbonate at a Salters Festival in a few years ago. Do the children need to be wearing gloves in this situation?
A few days I wrote about my worries about students wearing disposable gloves in the lab. I started discussing it with colleagues in the department, including several who sit on our safety committee. One of the comments that came out of these discussions was the number of incidents we’ve had over the past few years involving students transferring chemicals from their gloves to their face, neck, and elsewhere. In fact, if you stand and watch students in the lab – as I had occasion to this week – you see them contantly adjusting their safety specs and scratching their neck, nose, ears at regular intervals. All wearing gloves, of course. And because they are wearing the gloves, they are blissfully unaware that there might be anything on the outside of the glove.
The students, secondary school students, who were dissolving zinc in quite dilute HCl were, of course all wearing disposable gloves. It’s true that they had to boil the solution to driness, but it’s hard to imagine anyone getting hurt doing that, especially as the procedure was carried out in a fumehood. Nevertheless they were instructed to wear gloves in addition to safety glasses and lab coat. I stood around and watched. The students didn’t have much to do while the solutions boiled and they stood and chatted. Their hands went up and down, touching, fiddling with mobile phones, onto benches and, inevitably, onto their faces.
When I question them, the students were horrified at the suggestion that maybe they should take their gloves off. Until, that is, we talked about it, and during the coversation I’d drawn attention to the fact that each one of them had touched their chin, cheeks, neck etc. with the gloves. Not to mention their phones, their pens, their notebooks.
But in a way, with an aqueous solution, you know that the gloves are an actual barrier. But we don’t do that much aqueous chemistry. We use solvents. You should try this a simple experiment: squirt some solvents – acetone or dichloromethane, say – into some nitrile or latex gloves and then wait to see how you soon you could smell the solvent. When I did it last week, the answer was “instantly”. In other words the gloves (and you only have to do is look up the manufacturers’ specifications to see that this is the case) provide no protection at all. Indeed what they do is trap the solvent between the glove and you, giving your fingers a little more quality time to interact. Your hands being damp, you aren’t even aware that it’s happening.
In the labs our students get solvents on their gloves all the time, especially when washing up. It’s clearly nonsense. By providing gloves we are actually lulling our students into a false sense of security. They get stuff on their gloves and even if they’re aware of it, they just assume that because they have gloves on “it’s OK”. Risk compensation works in mysterious ways.
It’s very different if you don’t wear gloves. Today a colleague and I spent some time electrolyzing first molten potassium hydroxide (KOH), and then potassium carbonate at red heat (if you’re interested, it’s something to do with Brian “Delia” Cox). The spray from the bubbles generated in the electrolysis was intense and after a while everything was coated in a thick layer of KOH. We fiddled a little with the electrodes knowing full well that we had some ferociously caustic material a few centimeters from our hands. And while doing so, I got some KOH on my skin. It stings. It feels soapy. But the sink is there, right behind you. You rinse. It’s sorted.
Now I’m not saying that one shouldn’t wear gloves under any circumstance. Far from it. Clearly there are issues of scale and of context. But what I am saying is that for the vast majority of procedures like the ones we conduct in our teaching labs, gloves may look smart but they have precisely the opposite effect to what we intend.
It’s wrong, it’s wasteful, and it’s expensive. And we have plenty of, for the most part, fairly minor incidents to deal with that probably would not happen if our students didn’t wear them.
So the plan is to go even further and actively discourage students from wearing gloves as a matter of routine in our labs. Why? Because, completely contrary to “common sense”, we believe they’ll be safer and actually work better in the lab.
Will it catch on? I wonder. It’s not going to be easy.