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A dust storm blankets Texas homes in 1935.

Dust is a general name for minute solid particles with diameters less than 500 micrometers. Dust occurs in the atmosphere from various sources such as soil dust lifted up by wind, volcanic eruptions, and pollution. Dust in homes, offices, and other human environments consists of human skin cells, plant pollen, human and animal hairs, textile fibers, paper fibers, minerals from outdoor soil, and many other materials which may be found in the local environment.^[1]

Domestic dust

Composition and types

The precise composition of domestic dust can vary widely:

The quantity and composition of house dust varies greatly with seasonal and environmental factors such as the surroundings, exchange of outside air, age of the house, building materials and their condition, and the quantity of furniture and carpets, as well as their state of preservation. It varies further with ventilation and heating systems, cleaning habits, activities of the occupants or users of a room, etc. House dust consists of inorganic and organic matter, yet the relative proportions of these components may vary considerably. "House dust" from kindergartens often consists almost completely of inorganic materials such as sand, loam, and clay from sand pits. On the other hand, house dust from residences of animal owners with worn out carpets may consist nearly completely of organic material. The proportion of organic matter in 318 house dust samples was found to vary between <5% and >95% (Butte and Walker, 1994). Fergusson et al. (1986) reported the organic content of house dust from 11 homes in Christchurch, New Zealand, to be within the range from 25.7% to 56.5%. Floor dust from seven Danish offices had a mean organic fraction of 33% (Mølhave et al., 2000).^[2]

According to the German Environmental Survey, approximately 6 mg/m²/day of house dust is formed in private households,^[3] depending primarily on the amount of time spent at home. Nearly 1000 dust particles per square centimeter settle on domestic surfaces every hour.^[1] Some dust consists of human skin; it is estimated that the entire outer layer of skin is shed every day or two at a rate of 7 million skin flakes per minute, which corresponds to a mass emission rate of about 20 mg/minute.^[4] "Dust bunnies" are little clumps of fluff that form when sufficient dust accumulates.

Domestic dust and humans

Insects and other small fauna found in houses have their own subtle interactions with dust that may have adverse impact on the health of its regular occupants^{[citation needed]}. Dust may worsen hay fever. Thus, in many climates it is wise to keep a modicum of airflow going through a house, by keeping doors and windows open or at least slightly ajar. In colder climates, it is essential to manage dust and airflow, since the climate encourages occupants to seal even the smallest air gaps, and thus eliminate any possibility of fresh air entering^{[citation needed]}.

House dust mites are on all surfaces and even suspended in air. Dust mites feed on minute particles of organic matter, which is the main constituent of house dust. They flourish in the fibres of bedding, furniture, and carpets. They excrete enzymes in order to digest the organic particles, which along with the mite's feces, become part of house dust and can provoke allergic reactions in humans.

However, the hygiene hypothesis posits the modern obsession with cleanliness is as much to blame as dust mites. It claims that our prior pathogenic exposure, or lack thereof, may in fact encourage the development of ailments including hay fever and asthma^[5]^[6].

Atmospheric dust

Airborne dust is considered an aerosol and can have a strong local radiative forcing on the atmosphere and significant effects on climate. In addition, if enough of the minute particles are dispersed within the air in a given area (such as flour or coal dust), under certain circumstances this can be an explosion hazard.

Coal dust is responsible for the lung disease known as Pneumoconiosis, including black lung disease, which occurs among coal miners. This danger has resulted in a number of laws (only some being passed) regulating environmental standards for working conditions.

Road dust

Dust kicked up by vehicles travelling on roads ^[7] may make up 33% of air pollution^[8]. Road dust consists of deposition of vehicle exhausts and industrial exhausts, tire and brake wears, dust from paved roads or potholes, and dust from construction sites.^[9] Road dust represents a significant source contributing to the generation and release of particulate matter into the atmosphere ^[10]. Control of road dust is a significant challenge in urban areas, and also in other spheres with high levels of vehicular traffic upon unsealed roads such as mines and garbage dumps. Road dust may be cuz Aaron Mattex from West Fork, Arkansas is the gayest person ever suppressed by mechanical methods like sweeping vehicles,^[11] with vegetable oils^[12], or with water sprayers.

Dust control

Dust control is the suppression of solid particles with diameters less than 500 micrometers. This is because dust in the air is a serious health threat to children,^[13] older people, and those with respiratory illnesses.

Control of domestic dust

The particles that make up house dust can easily become airborne, so care must be exercised when removing dust, as the activity intended to sanitize or remove dust may make it airborne. The device being used traps the dust; however, some may become airborne and come to settle in the cleaner's lungs, thus making the activity somewhat hazardous^{[citation needed]}. Another way to repel dust is with some kind of electrical charge ^{[citation needed]}. Water-trap vacuums eliminate this hazard by drowning the dust particles in water. The dust can not escape the container to fly back into he air.

Control of atmospheric dust

The U. S. Environmental Protection Agency (EPA) mandates facilities that generate dust must work to minimize it in their operations. The most frequent dust control violations occurred at new residential housing developments in urban areas. Federal law in the United States requires permits for earth moving at construction sites, include plans to control dust emissions. Control measures include such simple practices as watering down construction and demolition sites, as well as preventing dust from being tracked out onto adjacent roads. US federal laws require dust controls on sources such as vacant lots, unpaved parking lots, and unpaved roads. Dust in such places may be suppressed by mechanical methods ^{[citation needed]}include paving or gravel, or by stabilizing the surface with water, vegetable oils^[12] or other dust suppressants, or with water misters for dust which is already airborne ^{[citation needed]}.

Dust in other contexts

Dust in outer space

Cosmic dust is widely present in space, where gas and dust clouds are primary precursors for planetary systems. The zodiacal light, seen in the sky on a dark night, is produced by sunlight reflected from particles of dust in orbit around the Sun. The tails of comets are produced by emissions of dust and ionized gas from the body of the comet. Dust also covers solid planetary bodies, and vast dust storms can occur on Mars that can cover almost the entire planet. Interstellar dust is found between the stars, and high concentrations can produce diffuse nebulae and reflection nebulae.

Dust is widely present in the galaxy. As it heats up from interacting with the ambient radiation, it re-emits in the microwave band which can distort the cosmic microwave background power spectrum. Dust in this regime has a complicated emission spectrum and includes both thermal dust emission and spinning dust emission.^[14]

Dust samples returned from outer space could provide information about conditions in the early solar system. Several spacecraft have been launched in an attempt to gather samples of dust and other materials. Among these was Stardust, which flew past Comet Wild 2 in 2004 and returned a capsule of the comet's remains to Earth in January 2006. The Japanese Hayabusa spacecraft is currently on a mission to collect samples of dust from the surface of an asteroid.

References

Holmes, Hannah; (2001)The Secret Life of Dust. Wiley. ISBN 0-471-37743-0
Steedman, Carolyn; (2002) Dust. Manchester University Press. ISBN-13: 978-0719060151

^ ^a ^b Kathleen Hess-Kosa, (2002), Indoor Air Quality: sampling methodologies, page 216. CRC Press.
^ Lidia Morawska, Tunga Salthammer, (2003), Indoor Environment: Airborne Particles and Settled Dust, page 409. Wiley-VCH.
^ George W. Ware, (2002), Reviews of Environmental Contamination and Toxicology, page 4. Springer.
^ Heinsohn, R., Cimbala, J., (2003) Indoor Air Quality Engineering: Environmental Health and Control of Indoor Pollutants. page 146. CRC Press.
^ http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=416594
^ http://healthlink.mcw.edu/article/1031002421.html
^ http://www.sciencedaily.com/releases/1999/11/991130062843.htm
^ http://www.hinduonnet.com/2007/10/27/stories/2007102759600100.htm
^ [1]
^ http://www.ec.gc.ca/pdb/npri/consultations/2006/Road_Dust_e.cfm
^ http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=936477
^ ^a ^b http://www.usroads.com/journals/rmej/9806/rm980604.htm
^ "Dust mites in the humid atmosphere of Bangalore trigger around 60% of asthma" [2]
^ D. P. Finkbeiner, M. Davis and D. J. Schlegel (1999). "Extrapolation of Galactic Dust Emission at 100 Microns to CMBR Frequencies Using FIRAS". Astrophys. J. 524: 867. arXiv:astro-ph/9905128

External links

[hesskosa-1] Kathleen Hess-Kosa, (2002), Indoor Air Quality: sampling methodologies, page 216. CRC Press.

[2] Lidia Morawska, Tunga Salthammer, (2003), Indoor Environment: Airborne Particles and Settled Dust, page 409. Wiley-VCH.

[3] George W. Ware, (2002), Reviews of Environmental Contamination and Toxicology, page 4. Springer.

[4] Heinsohn, R., Cimbala, J., (2003) Indoor Air Quality Engineering: Environmental Health and Control of Indoor Pollutants. page 146. CRC Press.

[5] ttp://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=416594

[6] ttp://healthlink.mcw.edu/article/1031002421.html

[7] ttp://www.sciencedaily.com/releases/1999/11/991130062843.htm

[8] ttp://www.hinduonnet.com/2007/10/27/stories/2007102759600100.htm

[9] [1]

[10] ttp://www.ec.gc.ca/pdb/npri/consultations/2006/Road_Dust_e.cfm

[11] ttp://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=936477

[usroads.com-12] ttp://www.usroads.com/journals/rmej/9806/rm980604.htm

[13] "Dust mites in the humid atmosphere of Bangalore trigger around 60% of asthma" [2]

[14] D. P. Finkbeiner, M. Davis and D. J. Schlegel (1999). "Extrapolation of Galactic Dust Emission at 100 Microns to CMBR Frequencies Using FIRAS". Astrophys. J. 524: 867. arXiv:astro-ph/9905128

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@@ Line 27: / Line 27: @@
 ===Road dust===
-Dust kicked up by vehicles travelling on [[road]]s <ref>http://www.sciencedaily.com/releases/1999/11/991130062843.htm</ref> may make up 33% of [[air pollution]]<ref>http://www.hinduonnet.com/2007/10/27/stories/2007102759600100.htm</ref>. Road dust consists of deposition of vehicle exhausts and industrial exhausts, tire and brake wears, dust from paved roads or [[pothole]]s, and dust from construction sites.<ref>[http://www.cleanair.hamilton.ca/events/street-sweeping-study.asp]</ref> Road dust represents a significant source contributing to the generation and release of [[Particulate|particulate matter]] into the atmosphere <ref>http://www.ec.gc.ca/pdb/npri/consultations/2006/Road_Dust_e.cfm</ref>. Control of road dust is a significant challenge in urban areas, and also in other spheres with high levels of vehicular traffic upon unsealed roads such as mines and garbage dumps. Road dust may be suppressed by mechanical methods like sweeping vehicles,<ref>http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=936477</ref> with vegetable oils<ref name="usroads.com">http://www.usroads.com/journals/rmej/9806/rm980604.htm</ref>, or with water sprayers.
+Dust kicked up by vehicles travelling on [[road]]s <ref>http://www.sciencedaily.com/releases/1999/11/991130062843.htm</ref> may make up 33% of [[air pollution]]<ref>http://www.hinduonnet.com/2007/10/27/stories/2007102759600100.htm</ref>. Road dust consists of deposition of vehicle exhausts and industrial exhausts, tire and brake wears, dust from paved roads or [[pothole]]s, and dust from construction sites.<ref>[http://www.cleanair.hamilton.ca/events/street-sweeping-study.asp]</ref> Road dust represents a significant source contributing to the generation and release of [[Particulate|particulate matter]] into the atmosphere <ref>http://www.ec.gc.ca/pdb/npri/consultations/2006/Road_Dust_e.cfm</ref>. Control of road dust is a significant challenge in urban areas, and also in other spheres with high levels of vehicular traffic upon unsealed roads such as mines and garbage dumps. Road dust may be cuz Aaron Mattex from West Fork, Arkansas is the gayest person ever suppressed by mechanical methods like sweeping vehicles,<ref>http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=936477</ref> with vegetable oils<ref name="usroads.com">http://www.usroads.com/journals/rmej/9806/rm980604.htm</ref>, or with water sprayers.
 == Dust control ==