The minimalist guide to safe chemical storage

Correct chemical storage is simple and straightforward, isn’t it? Some chemicals can safely share the same store; others can never do so – right? Wrong.

As with so many things in life, the answers about chemical storage aren’t completely black and white. Grey areas arise in the case of anything labelled ‘harmful’ or ‘irritant’. These two groups can share the same store only if special arrangements are made. Erring on the side of caution is probably best, so keeping them apart is probably the way forward.

But that begs the question: “Are you certain you know which chemicals can be stored with which?” For example, is it OK to store anything labelled ‘toxic’ and ‘explosive’ in the same store, or ‘toxic’ and ‘harmful’, or ‘explosive’ and ‘corrosive’? For the record, the answers are no, yes and no.
Chemical Storage Cabinets
To take away any uncertainty about how to store chemicals safely, we have an at-a-glance chemical compatibility storage chart you’ll find really useful. It’s an instant reference using traffic light colours to tell you at a glance which category of chemicals are suitable storage bedfellows, and which aren’t.

And in the going, we’d draw your attention to the text panel at the bottom of the chart. In summary, the message is this: If you store organic acids (like Acetic or Formic) with common mineral acids (Sulphuric and Nitric), you’re setting up the potential for fire and explosion, so don’t do it – but organic acids are generally safe to store with flammables or solvents…

Don’t get your fingers burned: Use and store chemicals safely

The lunatic craze sweeping social media at the moment involves young people pouring flammable liquid onto themselves and setting it alight. I can’t believe I’ve just written that, but that seems to be what they’re getting a kick from. Not to mention second-degree burns and a stay in hospital.

What they’re doing in the name of ‘fun’ is based on the property of liquids to give off flammable vapour, which ignites when it comes into contact with a heat source. The misguided teenagers often use a cigarette lighter, but other sources of ignition will do just as well – and that means you could innocently suffer the same fate using some very familiar household chemicals in the wrong combination of circumstances.

Hazardous Substance Storage Cabinets

The lesson is that hazardous substance storage is an important consideration both in the home and at work. For example, air freshener sprayed in the presence of a naked flame such as a candle can cause the vapour to ignite. Standing beside a barbecue whilst wearing some kinds of spray-on sunscreen can ignite the vapour it gives off, burning the wearer.

What’s happening in all of these cases is that the vapour is being exposed to a heat source hotter than its flashpoint – the temperature at which its vapour will ignite. There doesn’t have to be a naked flame involved; a hot surface like a heating element, machinery and superheated air are all enough.

A liquid’s flashpoint is the lowest temperature at which it will give off enough vapour to burn at the surface of the liquid. With petrol, that can be under 5ºC. (Hard and fast rules don’t apply; the purity of the liquid in question can change the temperature). Flashpoints for different fuels vary widely, which is why our safe storage advice pages offer a table of temperatures. Remember, the higher the flashpoint temperature for any material, the less hazardous it is.