Oil mist: Formation and dangers in industrial plants
In many industrial processes, especially in metalworking, the formation of oil mist is a problem that endangers the health of employees and impairs machine efficiency. To minimize these risks, measures to control and reduce oil mist are crucial.
Oil mist is created by the release of fine oil droplets into the air and leads to respiratory problems, skin irritation, and machine damage. Modern oil mist separators and extraction systems filter and remove the mist. These technologies help comply with legal limits and minimize workplace exposure, thereby ensuring employee health and operational efficiency.
What is oil mist?
Oil mist is created by the release of fine oil droplets into the air, forming an aerosol. These droplets are typically larger than one micrometer and consist of a heterogeneous mixture. Oil mist is released and spreads through the air, particularly during industrial processes such as the lubrication and cooling of machinery.
Cooling lubricants (also known as lubricants, emulsions, or coolants) consist of 90% to 95% water; the remainder is soluble oil. Oil mist is often visible, especially near the ceiling and in backlighting, and has a characteristic odor. Oil residue on surfaces indicates heavy oil mist exposure.
How is oil mist formed?
Oil mist is a common occurrence in manufacturing processes such as turning, milling, grinding, and drilling. In these processes, oil is atomized by rotating tools, particularly at high cutting speeds and injection pressures. Additionally, oil mist is generated by thermodynamic processes when liquids evaporate and disperse.
Other sources include the use of compressed air guns and the release of oil-laden air. Oil mist is generated not only during metalworking, but also in the plastics, rubber, textile, and steel industries, as well as in hardening plants. In all these sectors, industrial emissions contribute to air pollution.
Dangers from oil mist
Oil mist is a widespread phenomenon in industrial environments, posing both health and operational risks. The use of lubricants and coolants generates oil mist, which is released into the air as tiny aerosols and can significantly affect both people and machinery. The following overview highlights the most important health and operational risks.
What health hazards are posed by oil mist?
Oil mist poses a serious health risk to workers, especially those who come into regular contact with the fine particles. The most common health problems include the following:
1. Respiratory diseases (bronchitis, asthma, lung cancer)
- Chronic bronchitis and asthma: According to the German Social Accident Insurance (DGUV), respiratory illnesses such as chronic bronchitis and asthma frequently occur following exposure to oil mist. These are caused by the oil droplets penetrating deep into the lungs and their chemical additives (e.g., emulsifiers, preservatives).
- Lung cancer: A study by the International Agency for Research on Cancer (IARC) shows that long-term exposure to industrial aerosols, including oil mist, can increase the risk of lung cancer. Mineral oils used in metalworking, in particular, contain carcinogenic substances.
2. Skin and eye diseases (dermatitis, eye irritation)
- Dermatitis: According to the German Social Accident Insurance Institution for the Health and Welfare Services (BGW), direct contact with oil and its chemical additives, such as preservatives, can lead to skin diseases like dermatitis. Regular exposure over extended periods significantly increases the risk of developing dermatitis.
- Eye irritation: A study in Kluthe magazine emphasizes that oil mist can cause eye irritation and other mucous membrane problems, especially if the particles are small enough to penetrate the mucous membranes of the eyes.
3. Headaches and nausea
- Symptoms such as headaches and nausea: The Technical Rules for Hazardous Substances (TRGS 900) point out that chemical substances in oil mist, such as aromatic hydrocarbons and additives, can lead to acute symptoms such as headaches, dizziness, and nausea. This occurs particularly in poorly ventilated work areas.
What operational hazards arise from oil mist?
Oil mist poses significant operational hazards that can compromise both employee safety and the proper functioning of machinery. These hazards can have serious consequences for the production process and operating costs. Here are the key risks in detail:
1. Risk of slipping and accidents
Oil mist settles on surfaces such as floors, work areas, and machinery, making them slippery. This increases the risk of accidents, especially in industries with intensive machinery operation, where workers can easily slip or fall on slippery surfaces. Areas where oil droplets accumulate on walkways or work surfaces are particularly affected, as this can lead to serious injuries.
2. Machine breakdowns and increased maintenance costs
Fine oil mist particles accumulate on sensitive machine components and electronic devices, which can lead to malfunctions. These deposits can block mechanical parts or impair electrical systems, resulting not only in reduced performance but also in machine downtime. The increased exposure to oil mist necessitates more frequent maintenance to keep machines clean and operational. This, in turn, increases operating costs due to both downtime and maintenance expenses.
3. Fire hazard
Oil mist is highly flammable, especially near heat sources or sparks. In industries with hot machinery or welding operations, the risk of fire increases significantly, as the oil particles in the air or on surfaces can ignite. Even a small ignition source can cause fires if a sufficient amount of oil mist is present in the air.
4. Reduced machine efficiency
The deposition of oil mist on machine surfaces leads to increased frictional resistance and impairs machine functionality. Machines struggling with oil contamination operate more slowly and less efficiently, reducing the company's overall productivity. Furthermore, the contamination results in increased energy consumption, as the machines have to work harder to achieve the same output.
5. Electrical short circuits and damage
Electronic devices and control systems are particularly sensitive to oil mist. If oil particles penetrate electronic components, this can trigger short circuits or malfunctions. This is especially problematic in facilities that use sensitive machinery with complex electrical controls. Short circuits can lead to costly repairs and, in the worst-case scenario, fires.
6. Higher maintenance costs
The accumulation of oil mist on machinery and in work areas increases maintenance costs. Machines require more frequent cleaning to prevent downtime and malfunctions. The frequency and intensity of cleaning and maintenance work increase ongoing operating costs and can significantly impact productivity.
Can oil mist be measured?
Yes, oil mist can be detected using specialized measurement methods. Optical methods, such as opacity measurement, measure the haze caused by oil mist, while light scattering meters determine the particle size distribution. Gravimetric methods, in which oil droplets are collected on a filter and weighed, also offer a precise way to measure the concentration of oil mist, particularly for compliance with legal limits.
Electronic particle counters are also used, which record the number and size of particles in real time.
In Germany, an occupational exposure limit (OEL) of 5 mg/m³ applies, as specified in TRGS 900. This limit can vary depending on the type of cooling lubricant and is up to 10 mg/m³ for non-water-based substances.
Compliance with these limits is mandatory, and employers must carry out regular measurements to ensure that the concentration of oil mist does not reach dangerous levels.
Avoidance of oil mist
Avoiding oil mist requires technical, organizational, and process optimization measures. These include adjusting cutting speeds and optimizing coolant supply. Technical solutions such as high-performance extraction and filter systems, KAWEHA oil mist separators, and regular maintenance and filter replacement help to filter and separate oil mist.
Modern oil mist separators (also known as oil vapor separators or aerosol separators) utilize modular filter configurations that can be adapted to specific customer requirements. Activated carbon filters can be used to eliminate aromatics and odors. Alternative technologies such as minimum quantity lubrication or dry machining also contribute to reducing oil mist. These measures are part of general air pollution control, which aims to improve filtration technology in industries and thus promote environmental protection.
Oil mist separator from Kaweha
Kaweha's oil mist separators, such as our Oilmaster OM R , offer an efficient solution for separating oil and emulsion mists as well as aerosols in industrial applications. With a capacity range of 1,500 to 100,000 m³/h, our systems guarantee optimal workplace health protection thanks to their excellent filter technology. Designed for continuous operation in production environments, our oil extraction systems set new standards in air purification technology with their robust construction and minimal maintenance requirements. At Kaweha, we are committed to protecting the environment and employee health in the long term and ensuring maximum production efficiency.
September 13, 2024
