Chemical Safety in the Workshop
I was discussing the issue of storing dangerous chemicals in the workshop the other week with a work colleague and he took the attitude that as soon as his kids could walk he took everything out of the garden shed and outsourced all such activities (such as fertilising the lawn) to professionals. Victor Deeb on the other hand took the opposite extreme view and thought it a good idea to keep “over 1,500 vials, jars, and bottles of chemicals” in his basement and garage and in Birmingham a shed full of acetylene and diesel caught on fire requiring the neighbourhood to be evacuated.
The sensible approach is somewhere between these two extremes, it is possible to keep and use chemicals in your workshop and also keep yourself (and others) safe.
You might be surprised just how many dangerous chemicals you have in your workshop. Here’s my quick shortlist. Many of these items will are common in all households but a few are old used for model engineering.
- Cleaning Materials
- Solvents, Polish and Paints
- Gasses – Propane/Butane/MAPP Gas
- Oils and cutting fluids
What are the kinds of problems you might get with these materials and what can you do about them?
- Flammable items
- Caustic items
- Changes in temperature
- Bacterial contamination of fluids
There are many flammable items in the workshop, some are flammable by design such as matches, firelighters and fuel but others such as solvents are also flammable. When not in use you need to keep such items stored out of possible contact with sources of sparks (such as a grinder), out of the sun and well sealed so that they don’t evaporate.
Caustic chemicals include cleaning chemicals, acids used for pickling, and fluxes. You need to be careful handling these to ensure you don’t get them on your skin or in your eyes.
Some materials are reasonably safe on their own but when mixed can become significantly more dangerous or will react generating heat or rapidly expanding in volume. Hence it’s important not to mix chemicals when storing or disposing of them.
In the same way that some materials react with each other, they might also react with light. Sometimes they just “go off” for example if you use nut oil for heat treatments but they may also expand or explode as the summer run heats up that can of petrol for example.
Ambient temperature changes may have a similar effect to the sun. You also need to be aware that if your workshop temperature drops below freezing then any water based liquids stored in bottles will expand and might cause the bottle to smash. Often this issue is not spotted until the liquid thaws out again.
Water by itself is not too hazardous however some powdered chemicals can react with water, particularly if it is not pure (e.g. rain or flood water). You also need to be aware that water might soak through cardboard boxes. Water poluted with chemicals can seep into the ground and cause additional hazards to either you or the environmemt.
Given these above issues, your storage needs to be suitable for the chemicals being stored. A secure, fire retardant, light proof cupboard or box is recommended. You need to ensure it is not going to be flooded or rained on. The cupboard should be vented so that any fumes dissipate rather than build up. Any containers or pots should be clearly labelled as being chemicals rather than being labelled as “Jam” or “Cola”.
Apart from the kids mistaking your bags of flux for sherbet dips there are several other ways people can be poisoned by chemicals. It’s also possible to inhale dust, spray or gasses or absorb the chemicals through the skin or through cuts. Transfer of chemicals from the hands to mouth is also possible. Appropriate safety gear can reduce risk. Hopefully you’ll research your chemicals before you have problems but the NHS recommendation is to ring 999 in any suspected poisoning case, try to get the following for them:
- what substances you think the person may have swallowed,
- when the substance was taken (how long ago),
- how it was taken (for example, swallowed), and
- how much was taken (if known).
One problem that can occur in a machineshop is that the your cutting/cooling fluid gets contaminated with bacteria. This can then be ingested when it sprays up when machining or via transfer from hands. Symptoms are like those of a cold, but they may not go away. Don’t leave water based cutting fluid “made up” for long periods of time or store it in open containers. You can also get additives to suppress growth of bacteria.
In the same way that you don’t want your family to be poisoned, you don’t want pets to affected. Storage is key here, remember that paws are smaller than hands! You also want to ensure that your storage is secure from rodents or bugs that might feast on the chemicals.
Your local council should be able to help with disposal or recycling of used or surplus chemicals, see the link below for more details and ideas.
My final thought is that all of the above issues become less significant if you have less chemicals to start with. Do you really need 12 different kinds of flux? Do you need 100L of cutting fluid if you only make watches? If a supplier only sells in bulk then see if you can find some people at your local model club who can split an order.