Oil mist refers to

oil An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) & lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturated ...

droplets suspended in the air in the size range 1~10 μm.

Formation of Oil Mist

Oil mist may form when high pressure

fuel oil Fuel oil is any of various fractions obtained from the distillation of petroleum (crude oil). Such oils include distillates (the lighter fractions) and residues (the heavier fractions). Fuel oils include heavy fuel oil, marine fuel oil (MFO), b ...

lubricating oil A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, t ...

hydraulic oil A hydraulic fluid or hydraulic liquid is the medium by which power is transferred in hydraulic machinery. Common hydraulic fluids are based on mineral oil or water. Examples of equipment that might use hydraulic fluids are excavators and backhoes, ...

, or other oil is sprayed through a narrow crack, or when leaked oil connects with a high temperature surface, vaporizes, and comes in contact with low air temperature. This happens while the fluids interact with the moving parts during

machining Machining is a process in which a material (often metal) is cut to a desired final shape and size by a controlled material-removal process. The processes that have this common theme are collectively called subtractive manufacturing, which utilizes ...

. Smaller oil droplets than oil mist are difficult to generate under normal circumstances. Bigger oil droplets than oil mist remain in spray form; this has the advantage of a higher ignition temperature. It sinks easily, reducing

fire Fire is the rapid oxidation of a material (the fuel) in the exothermic chemical process of combustion, releasing heat, light, and various reaction products. At a certain point in the combustion reaction, called the ignition point, flames ...

hazard. Oil mist inside the crankcase can cause a bigger problem.

Risks

When the concentration of oil mist increases and reaches the

lower explosion limit Mixtures of dispersed combustible materials (such as gaseous or vaporised fuels, and some dusts) and oxygen in the air will burn only if the fuel concentration lies within well-defined lower and upper bounds determined experimentally, referred to a ...

(LEL; 50 mg/ℓ, as defined by the IACS), explosion may occur when the mist contacts surfaces of over or a spark. The

International Association of Classification Societies The International Association of Classification Societies (IACS) is a technically based non-governmental organization that currently consists of eleven member marine classification societies. More than 90% of the world's cargo-carrying ships’ ton ...

(IACS) mandates that all ships with a cylinder diameter greater than 300mm or

engine power Engine power is the power that an engine can put out. It can be expressed in power units, most commonly kilowatt, pferdestärke (metric horsepower), or horsepower. In terms of internal combustion engines, the engine power usually describes the ' ...

over 2,250 kW must be equipped with either bearing temperature detectors or oil mist detectors. In regards to occupational exposures, the

Occupational Safety and Health Administration The Occupational Safety and Health Administration'' (OSHA ) is a large regulatory agency of the United States Department of Labor that originally had federal visitorial powers to inspect and examine workplaces. Congress established the agen ...

and the

National Institute for Occupational Safety and Health The National Institute for Occupational Safety and Health (NIOSH, ) is the United States federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. NIOSH is part of the C ...

have set occupational exposure limits at 5 ppm over an eight-hour time-weighted average, with a

short-term exposure limit A short-term exposure limit (STEL) is the acceptable average exposure over a short period of time, usually 15 minutes as long as the time-weighted average is not exceeded. STEL is a term used in occupational health, industrial hygiene and toxicolo ...

at 10 ppm.CDC - NIOSH Pocket Guide to Chemical hazards
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Related accidents

2010 Puebla oil pipeline explosion The 2010 Puebla oil pipeline explosion was a large oil pipeline explosion that occurred at 5:50 am CST on December 19, 2010, in the city of San Martín Texmelucan de Labastida, Puebla, Mexico. The pipeline, running from Tabasco to Hidalgo, was ...

: The 2010 Puebla oil pipeline explosion was a large

oil pipeline Pipeline transport is the long-distance transportation of a liquid or gas through a system of pipes—a pipeline—typically to a market area for consumption. The latest data from 2014 gives a total of slightly less than of pipeline in 120 count ...

explosion in

Mexico Mexico (Spanish language, Spanish: México), officially the United Mexican States, is a List of sovereign states, country in the southern portion of North America. It is borders of Mexico, bordered to the north by the United States; to the so ...

. In the central part of Mexico, 28 people were killed by the explosion.

References

External links

1 International Maritime Organization (IMO)
GUIDELINES FOR THE MANUFACTURE AND INSTALLATION OF OIL MIST DETECTORS

CODE OF PRACTICE FOR ATMOSPHERIC OIL MIST DETECTORS
2 International Association of Classification Societies Ltd unified requirements concerning MACHINERY INSTALLATIONS *M10 Protection of internal combustion engines against crankcase explosions *M6
Type Testing Procedure for Crankcase Oil Mist Detection and Alarm Equipment
3 Oil Companies International Marine Forum Ship Inspection Report (SIRE) Programme/ Vessel Inspection Questionnaires for Oil Tankers, Combination Carriers, Shuttle Tankers, Chemical Tankers and Gas Carriers
Questions & Answers : 11.22 / 11.23 / 11.24 / 11.25
{Dead link, date=April 2020 , bot=InternetArchiveBot , fix-attempted=yes Oils