Machining workshops use fluids to cool and lubricate metal when it’s being machined, drilled, milled etc. But what’s good for the work process is not so healthy for the lungs and skin.
Metalworking fluid (MWF) is the collective name given to oils, water-based fluids, pastes, gels and aerosols used during the machining of metal. They may also be referred to as cutting fluids. MWF reservoirs can become breeding grounds for bacteria. The substances also attract metal contaminants from the machines and contain chemicals such as corrosion inhibitors and biocides. As a result of these substances getting into the air and onto surfaces, workers may suffer ill health. Lung diseases associated with MWF include asthma, bronchitis, irritation of the upper respiratory tract and allergic inflammation of the alveoli in the deep lung.
Fully enclosing the machining area and installing local exhaust ventilation (LEV) is the most effective strategy for managing this risk, although this may not suit all businesses due to both space and cost constraints.
Many computer-controlled machines will have this type of arrangement in place as standard. If this applies to your workplace, ensure that you know how to maintain the system and that the MWF delivery system stops between operations.
You can use a smoke tube to track air movement, showing how long the enclosure must remain closed for after machining in order to contain most of the mist. Smoke tubes are readily available from gas detection and monitoring supply companies and work by simple action of breaking the tube, generating white smoke.
Regardless of the complexity of your machines there are easy to implement measures which will reduce the risks.
Check that your machine is not delivering an excessive amount of MWF, for example, it shouldn’t be settling on every surface. Adjust the flow rate so that it’s just enough, but not too much.
The use of compressed air to clean components after machining is common, however this increases the risk of inhaling MWF. Where no practicable alternative is available, reduce exposure, e.g using airlines with longer handles and with shields fitted, and reduce air pressure to the minimum. It’s likely LEV and/or respiratory protection will be needed.
You’ll need to carry out a risk assessment under the Control of Substances Hazardous to Health Regulations 2002 to ensure that your risk measures are adequate. Since this is a technical area, if you don’t have in-house expertise you might want to obtain assistance from an occupational hygienist.
Include daily checks, cleaning, topping up etc. of MWF and LEV systems on your routine maintenance schedule.
Should you need further help or guidance on this issue, please don’t hesitate to contact our Health & Safety team.