What is Oil Smoke and Oil Mist
Oil mist and oil smoke arise in a number of various manufacturing operations. Before we can take the correct measures to overcome the risks and harm that these substances cause, we need to know specifically what oil mist and oil smoke really are.
In the manufacturing industry, oil mist arises especially during metal-cutting machining, which is a comprehensive term for turning, milling, grinding and boring, etc. Oil mist arises when oil or water mixed with concentrated cutting fluid, so-called emulsion, is used for cooling, lubricating or chip removal.
From oil mist to oil smoke
With high speed and pressure, the oil drops get very small
(‹1 µm) and the amount of oil in the air is often high. In such
operations, oil smoke occurs in a larger scale.
As machining operations are carried out, these fluids are emitted in the form of aerosols and smoke to the surrounding air. It is, of course, unhealthy to breathe these substances.
The National Board of Occupational Safety and Health has therefore drawn up specific limit values for this. The current limit value for the emission of aerosols to industrial premises is 1 mg/m3.
What are the risks?
The risks that are most often associated with large concentrations
of oil mist or oil smoke are the following:
• Oil mist can contain small metallic particles that can give
rise
to respiratory problems.
• Skin problems, including oil acne and eczema
• Increased risk of slipping – oil mist eventually settles on
the floor.
• Deteriorated indoor air caused by oil accumulating on surfaces
inside the ventilation system impairing its function and fouling
the air.
• Generally unclean environment due to the oil attracting other
impurities causing them to stick to machines and other equipment.
• Aerosols harm the electronics in modern metalworking machines.
How to deal with oil mist and
oil smoke problems?
The most common and effective method of collecting oil mist
/ oil smoke is at the source, i.e. directly at the metalworking
machine. This is possible both in the case of completely enclosed
machines and open machines.
In an enclosed machine, sub-atmospheric pressure is created in the space where the machining operations take place. The oil-laden air is sucked out of the enclosure and conveyed through a duct to the filter unit. After the air has been filtered, it is returned to the premises or flows further to a heat exchanger.
If open machines are installed, it is common to try to capture
oil mist/smoke in some kind of hood or superstructure and from
there convey it through a duct to the filter unit.
