Gloves can provide good protection if used correctly, but conversely may give a false sense of security if used incorrectly. It is normally advisable to wear disposable gloves whenever you handle chemicals, to protect against splashes, and whenever you handle animals, to protect against disease.
In order to use gloves properly you need to think while you work. Discard the gloves if chemicals got inside them. Change your gloves often, and take the gloves off before you touch anything else, eg. answer your phone, open a door, or use a pencil or computer.
All gloves are designed to be tight. This means that the sweat from your hand stays in the glove, leading to softening of the skin which reduces its natural barrier properties. Moisture in the glove, plus powder, plus any other substances quickly creates a bad environment for your hands — which is why we recommend that you put on a cotton glove under the disposable gloves whenever the work is expected to take a while.
Traces of latex proteins from latex gloves can cause extra problems. Manufacturers are constantly improving their products, so you can now get extra, extra rinsed latex gloves.
Ideally, ensure only contact between the gloves and chemicals. We normally use only disposable gloves, which must be changed if contaminated.
Types of gloves:
At the Institute, we now have 3 types of chemical gloves, to cover all normal uses. Other types can be ordered if necessary.
Vinyl gloves are made of PVC plastic, which has little chemical resistance. Vinyl gloves can be used for handling acids and alkalis, oils, fats and chemicals in powder form. Vinyl gloves are also suitable for handling laboratory animals.TNT Blue:
Touch'n tuff (TNT) gloves are made of 100% nitrile without additives. TNT Blue gives a good grip and good but time-limited chemical resistance.Barrier:
A barrier-glove is a multi-layer glove that is built up of polyethylene and nylon. This glove is the successor to the not very comfortable 4H-glove, with improved ergonomy and comfort. It is still very clumsy, but can be used with a latex glove on the outside to give better sensitivity. Barrier-gloves have a higher chemical resistance than other similar gloves.
Choosing the right gloves
Different types of gloves protect against different substances, so take care to choose the right type of glove for the work you are doing.
Normally your choice is determined by the glove's resistance to the chemical or the mixture you wish to protect yourself against. Typically, protection level is measured in breakthrough time. Breakthrough time is defined as the elapsed time in minutes from when the chemical contacts the outer surface to when the chemical can be detected on the inner surface. The higher the breakthrough time, the better protection you receive.
The next key data to look at is the permeation rate. This gives the rate the chemical penetrates the glove. This is measured in milligrams per square meter per second. The slower the rate, the better protection the glove provides. The ideal protective glove will show no permeation rate detected.
Note that these numbers vary according to the chemical being tested, and also vary for different manufacturers as well as different glove types. Tables of data for different gloves and different chemicals can be obtained from the supplier and is available on their websites, eg ansell.dk Be aware that mixtures often behave differently from pure chemicals!
At the Institute we only buy gloves which are tested according to European standards on protective gloves. The following can be found on the box:
CE mark is a guarantee that European standards are met. 0493 is the ID number of the independent monitoring institution, which has tested the glove. The pictograms indicate that glove is tested for chemical resistance and microorganism penetration.
It is impossible to say that certain types of gloves are suitable for work with specific groups of substances or chemicals. Therefore you need to ascertain how chemicals behave with the particular glove separately for each case. This can be seen in the glove manufacturer's comments or on the safety data sheets for the chemical. If in doubt, you can contact your OSH representative, who may be able to retrieve additional information about gloves and chemicals from other databases.
If you minimise the contact between chemicals and gloves as recommended, then you can normally work using only the normal disposable gloves. It is then only necessary to do serious research on the different glove types and their relevance to your work if you work with particularly dangerous and reactive substances. You can always run your own tests, if the data you need is not readily available.