PREVENTING KEROSENE FIRES AT HOME

Kerosene has been an important household fuel since the mid-19th century. In developed countries its use has greatly declined because of electrification. However, in developing countries, kerosene use for cooking and lighting remains widespread. This review focuses on household kerosene uses, mainly in developing countries, their fire hazards in the case of adulteration of the product. Kerosene is often advocated as a cleaner alternative to solid fuels, biomass and coal, for cooking, and kerosene lamps are frequently used when electricity is unavailable. Globally, an estimated 500 million households still use fuels, particularly kerosene, for lighting.

Kerosene, also spelled kerosine, also called paraffin or paraffin oil, flammable hydrocarbon liquid commonly used as a fuel. Kerosene is typically pale yellow or colourless and has a not-unpleasant characteristic odour. It is obtained from petroleum and is used for burning in kerosene lamps and domestic heaters or furnaces, as a fuel or fuel component for jet engines, and as a solvent for greases and insecticides.

BURNS AND FIRES

Relative to gasoline or LPG, kerosene has a low vapor pressure (high flashpoint) at ambient conditions, reducing the risk of explosion from volatilization into indoor environments. The viscosity is also low enough that kerosene will easily wick up absorbent materials. Nonetheless, kerosene appliances are responsible for many fires and burns, with a variety of contributing factors. As the problem of kerosene-related fires and burns has been recently reviewed (Peck et al. 2008), only the main features are summarized here.

Both kerosene stoves and lamps have led to major fires and serious, often fatal, burns. Exacerbating the problem, these devices are often used in confined spaces in poor, crowded communities, such as slums, where dwellings are packed together and often made of wood and cardboard. Kerosene stoves are often placed on the floor and easily knocked over, particularly by children, causing kerosene spillage and a rapidly spreading fire. Women, who predominantly do the cooking, often wear loose-fitting flammable clothing. A gust of air may suddenly increase wick flame size, igniting clothing.

Many devices, particularly those with wicks, are poorly constructed and leak. The leakage may ignite. Explosions can result from the mixing of gasoline with kerosene. This can arise, for example, from use of the same container for the two fuels. Even a small amount of gasoline, with its much lower flash-point and higher vapor pressure, mixed with kerosene can lead to kerosene devices exploding. Another common cause of fires and explosions is adding more kerosene fuel to a device when it is lit.

Manufactured pressure lamps suffer from blocking of nozzles by soot. This may lead to attempts to increase flame size by pumping the fuel to higher pressure. Subsequent attempts to clear the nozzle with a pin or wire can cause a sudden high-pressure release of an air–fuel mixture, with resulting explosion.

Flash point testing is important for a variety of product applications and there are several specific tests designed to measure flash point. Because of slight variations within these test methods, whenever flash point is reported, the test method used should be reported along with the value. Flash point has been defined in Subsection 4.6.6 as “the lowest temperature at which a substance generates a sufficient amount of vapor to form a (vapor/air) mixture that can be ignited.” It should be added that this lowest temperature is determined through specific laboratory tests.

Cleveland Open Cup (COC)

This test procedure utilizes an open metal container that is filled with the sample oil. The oil is then heated at a prescribed rate and periodically a small pilot flame (ignitor) is passed over its surface. This continues until a flash appears.

The oil temperature is then recorded as its flash point. The procedure is the most widely used in presenting a new lubricant’s physical and chemical properties. In the used oil analysis lab however, the procedure can require more oil than typically available and an exceedingly long test time.

And, for fuel dilution the lower limit of sensitivity may be inadequate because, being open, it does not retain the vapors long enough to get a flash.

Pensky-Marten Closed Cup

With this test, the sample is confined in a closed container into which the pilot flame is periodically introduced. Additionally, the lubricant is agitated during the heating period and the lowest temperature at which a flash appears is recorded.

As with the COC method, a considerable amount of fluid and time is needed to perform the test. However, fully automated instruments are available from various suppliers. In measuring fuel dilution, one advantage the Pensky-Marten has over the COC method is improved sensitivity to lower concentrations of fuel dilution.

Small Scale Closed Tester

This small-scale flash point tester goes by various names (e.g., mini-flash) and is perhaps the most adaptable for routine used oil analysis. While both the Pensky-Marten and COC can be used as a pass/fail tester, this procedure accomplishes the screening test (Method A) with only 2ml of fluid in just 1-2 minutes.

The finite flash point can also be obtained (Method B) but more fluid and time are needed. It is also worth noting that both the repeatability and reproducibility of this procedure is distinctly better than the previous two tests . Many high-production used oil analysis labs use this procedure with auto sampling in the pass/fail mode in screening for fuel dilution.

Reference:

Peck MD, Kruger GE, van der Merve A, Godakumbura W, Ahuja RB. Burns and fires from non-electric domestic appliances in low and middle income countries. Part 1 The scope of the problem. Burns. 2008;34:303–11. [PubMed] [Google Schola