Sanitation - AbsoluteAstronomy.com

Sanitation is the hygienic

Hygiene

Hygiene refers to the set of practices perceived by a community to be associated with the preservation of health and healthy living. While in modern medical sciences there is a set of standards of hygiene recommended for different situations, what is considered hygienic or not can vary between...

means of promoting health

Health promotion

Health promotion has been defined by the World Health Organization's 2005 Bangkok Charter for Health Promotion in a Globalized World as "the process of enabling people to increase control over their health and its determinants, and thereby improve their health"...

through prevention

Hazard prevention

Hazard prevention refers to the prevention of risks. The first and most effective stage of hazard prevention and emergency management is the elimination of hazards...

of human contact with the hazard

Hazard

A hazard is a situation that poses a level of threat to life, health, property, or environment. Most hazards are dormant or potential, with only a theoretical risk of harm; however, once a hazard becomes "active", it can create an emergency situation. A hazard does not exist when it is not...

s of waste

Waste

Waste is unwanted or useless materials. In biology, waste is any of the many unwanted substances or toxins that are expelled from living organisms, metabolic waste; such as urea, sweat or feces. Litter is waste which has been disposed of improperly...

s. Hazards can be either physical, microbiological, biological or chemical agents of disease. Wastes that can cause health problems are human and animal feces, solid wastes, domestic wastewater (sewage, sullage, greywater), industrial wastes and agricultural wastes. Hygienic means of prevention can be by using engineering solutions (e.g. sewerage and wastewater treatment

Wastewater Treatment

Wastewater treatment may refer to:* Sewage treatment* Industrial wastewater treatment...

), simple technologies (e.g. latrines, septic tanks), or even by personal hygiene practices (e.g. simple handwashing

Hand washing

Hand washing for hand hygiene is the act of cleaning the hands with or without the use of water or another liquid, or with the use of soap, for the purpose of removing soil, dirt, and/or microorganisms....

with soap).

Overview

The World Health Organization

World Health Organization

The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...

states that:
The term "sanitation" can be applied to a specific aspect, concept, location or strategy, such as:

Basic sanitation - refers to the management of human faeces at the household level. This terminology is the indicator used to describe the target of the Millennium Development Goal on sanitation.
On-site sanitation - the collection and treatment of waste is done where it is deposited. Examples are the use of pit latrine
Latrine
A latrine is a communal facility containing one or more commonly many toilets which may be simple pit toilets or in the case of the United States Armed Forces any toilet including modern flush toilets...

s, septic tank
Septic tank
A septic tank is a key component of the septic system, a small-scale sewage treatment system common in areas with no connection to main sewage pipes provided by local governments or private corporations...

s, and Imhoff tank
Imhoff tank
The Imhoff tank, named for German engineer Karl Imhoff , is a chamber suitable for the reception and processing of sewage. It may be used for the clarification of sewage by simple settling and sedimentation, along with anaerobic digestion of the extracted sludge...

s.
Food sanitation - refers to the hygienic measures for ensuring food safety
Food safety
Food safety is a scientific discipline describing handling, preparation, and storage of food in ways that prevent foodborne illness. This includes a number of routines that should be followed to avoid potentially severe health hazards....

.
Environmental sanitation - the control of environmental factors that form links in disease transmission. Subsets of this category are solid waste management, water and wastewater treatment, industrial waste treatment and noise and pollution control.
Ecological sanitation
Ecological sanitation
Ecological sanitation, also known as ecosan or eco-san, are terms coined to describe a form of sanitation that usually involves urine diversion and the recycling of water and nutrients contained within human wastes back into the local environment....

- an approach that tries to emulate nature through the recycling of nutrients and water from human and animal wastes in a hygienically safe manner.

History

The earliest evidence of urban sanitation was seen in Harappa

Harappa

Harappa is an archaeological site in Punjab, northeast Pakistan, about west of Sahiwal. The site takes its name from a modern village located near the former course of the Ravi River. The current village of Harappa is from the ancient site. Although modern Harappa has a train station left from...

, Mohenjo-daro

Mohenjo-daro

Mohenjo-daro is an archeological site situated in what is now the province of Sindh, Pakistan. Built around 2600 BC, it was one of the largest settlements of the ancient Indus Valley Civilization, and one of the world's earliest major urban settlements, existing at the same time as the...

and the recently discovered Rakhigarhi

Rakhigarhi

Rakhigarhi, or Rakhi Garhi , is a village in Hisar District in the northwest Indian state of Haryana, around 150 kilometers from Delhi. In 1963 archeologists discovered the village was the site of an extensive city, part of the Indus Valley Civilization...

of Indus Valley civilization

Indus Valley Civilization

The Indus Valley Civilization was a Bronze Age civilization that was located in the northwestern region of the Indian subcontinent, consisting of what is now mainly modern-day Pakistan and northwest India...

. This urban plan included the world's first urban sanitation systems. Within the city, individual homes or groups of homes obtained water from wells

Water well

A water well is an excavation or structure created in the ground by digging, driving, boring or drilling to access groundwater in underground aquifers. The well water is drawn by an electric submersible pump, a trash pump, a vertical turbine pump, a handpump or a mechanical pump...

. From a room that appears to have been set aside for bathing, waste water was directed to covered drains, which lined the major streets.

Roman

Ancient Rome

Ancient Rome was a thriving civilization that grew on the Italian Peninsula as early as the 8th century BC. Located along the Mediterranean Sea and centered on the city of Rome, it expanded to one of the largest empires in the ancient world....

cities and Roman villa

Roman villa

A Roman villa is a villa that was built or lived in during the Roman republic and the Roman Empire. A villa was originally a Roman country house built for the upper class...

s had elements of sanitation systems, delivering water in the streets of towns such as Pompeii

Pompeii

The city of Pompeii is a partially buried Roman town-city near modern Naples in the Italian region of Campania, in the territory of the comune of Pompei. Along with Herculaneum, Pompeii was destroyed and completely buried during a long catastrophic eruption of the volcano Mount Vesuvius spanning...

, and building stone and wooden drains to collect and remove wastewater

Wastewater

Wastewater is any water that has been adversely affected in quality by anthropogenic influence. It comprises liquid waste discharged by domestic residences, commercial properties, industry, and/or agriculture and can encompass a wide range of potential contaminants and concentrations...

from populated areas - see for instance the Cloaca Maxima

Cloaca Maxima

The Cloaca Maxima is one of the world's earliest sewage systems. Constructed in Ancient Rome in order to drain local marshes and remove the waste of one of the world's most populous cities, it carried an effluent to the River Tiber, which ran beside the city....

into the River Tiber in Rome. But there is little record of other sanitation in most of Europe until the High Middle Ages

High Middle Ages

The High Middle Ages was the period of European history around the 11th, 12th, and 13th centuries . The High Middle Ages were preceded by the Early Middle Ages and followed by the Late Middle Ages, which by convention end around 1500....

. Unsanitary conditions and overcrowding were widespread throughout Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

and Asia

Asia

Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

during the Middle Ages

Middle Ages

The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...

, resulting periodically in cataclysmic pandemic

Pandemic

A pandemic is an epidemic of infectious disease that is spreading through human populations across a large region; for instance multiple continents, or even worldwide. A widespread endemic disease that is stable in terms of how many people are getting sick from it is not a pandemic...

s such as the Plague of Justinian

Plague of Justinian

The Plague of Justinian was a pandemic that afflicted the Eastern Roman Empire , including its capital Constantinople, in 541–542 AD. It was one of the greatest plagues in history. The most commonly accepted cause of the pandemic is bubonic plague, which later became infamous for either causing or...

(541-42) and the Black Death

Black Death

The Black Death was one of the most devastating pandemics in human history, peaking in Europe between 1348 and 1350. Of several competing theories, the dominant explanation for the Black Death is the plague theory, which attributes the outbreak to the bacterium Yersinia pestis. Thought to have...

(1347–1351), which killed tens of millions of people and radically altered societies.

Very high infant and child mortality prevailed in Europe throughout medieval times, due not only to deficiencies in sanitation but to an insufficient food supply for a population which had expanded faster than agriculture

Agriculture

Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

. This was further complicated by frequent warfare and exploitation of civilians by autocratic rulers.

Wastewater collection

The standard sanitation technology in urban areas is the collection of wastewater

Wastewater

in sewers, its treatment in wastewater treatment plants

Sewage treatment

Sewage treatment, or domestic wastewater treatment, is the process of removing contaminants from wastewater and household sewage, both runoff and domestic. It includes physical, chemical, and biological processes to remove physical, chemical and biological contaminants...

for reuse

Reuse

To reuse is to use an item more than once. This includes conventional reuse where the item is used again for the same function, and new-life reuse where it is used for a different function. In contrast, recycling is the breaking down of the used item into raw materials which are used to make new...

or disposal in rivers, lakes or the sea. Sewers are either combined with storm drain

Storm drain

A storm drain, storm sewer , stormwater drain or drainage well system or simply a drain or drain system is designed to drain excess rain and ground water from paved streets, parking lots, sidewalks, and roofs. Storm drains vary in design from small residential dry wells to large municipal systems...

s or separated from them as sanitary sewer

Sanitary sewer

A sanitary sewer is a separate underground carriage system specifically for transporting sewage from houses and commercial buildings to treatment or disposal. Sanitary sewers serving industrial areas also carry industrial wastewater...

s. Combined sewers are usually found in the central, older parts or urban areas. Heavy rainfall

Stormwater

Stormwater is water that originates during precipitation events. It may also be used to apply to water that originates with snowmelt that enters the stormwater system...

and inadequate maintenance can lead to combined sewer overflows or sanitary sewer overflow

Sanitary sewer overflow

Sanitary sewer overflow is a condition whereby untreated sewage is discharged into the environment prior to reaching treatment facilities thereby escaping wastewater treatment. When caused by rainfall it is also known as wet weather overflow. It is primarily meaningful in developed countries,...

s, i.e. more or less diluted raw sewage

Sewage

Sewage is water-carried waste, in solution or suspension, that is intended to be removed from a community. Also known as wastewater, it is more than 99% water and is characterized by volume or rate of flow, physical condition, chemical constituents and the bacteriological organisms that it contains...

being discharged into the environment. Industries often discharge wastewater into municipal sewers, which can complicate wastewater treatment unless industries pre-treat their discharges.

The high investment cost of conventional wastewater collection systems are difficult to afford for many developing countries. Some countries have therefore promoted alternative wastewater collection systems such as condominial sewerage, which uses smaller diameter pipes at lower depth with different network layouts from conventional sewerage.

Wastewater treatment

In developed countries treatment of municipal wastewater is now widespread, but not yet universal (for an overview of technologies see wastewater treatment

Wastewater Treatment

Wastewater treatment may refer to:* Sewage treatment* Industrial wastewater treatment...

). In developing countries most wastewater is still discharged untreated into the environment. For example, in Latin America only about 15% of collected sewerage is being treated (see water and sanitation in Latin America)

Reuse of wastewater

The reuse of untreated wastewater in irrigated agriculture

Irrigation

Irrigation may be defined as the science of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall...

is common in developing countries. The reuse of treated wastewater in landscaping, especially on golf courses, irrigated agriculture and for industrial use is becoming increasingly widespread.

In many suburban and rural areas households are not connected to sewers. They discharge their wastewater into septic tanks or other types of on-site sanitation.

Ecological sanitation

Ecological sanitation, also known as ecosan or eco-san, are terms coined to describe a form of sanitation that usually involves urine diversion and the recycling of water and nutrients contained within human wastes back into the local environment....

is sometimes presented as a radical alternative to conventional sanitation systems. Ecological sanitation is based on composting

Composting toilet

A composting toilet is a dry toilet that using a predominantly aerobic processing system that treats excreta, typically with no water or small volumes of flush water, via composting or managed aerobic decomposition...

or vermicomposting toilets where an extra separation of urine and feces at the source for sanitization and recycling has been done. It thus eliminates the creation of blackwater

Blackwater (waste)

Blackwater is a term dating to at least the 1970s used to describe wastewater containing fecal matter and urine. It is also known as brown water, foul water, or sewage...

and eliminates fecal pathogens. If ecological sanitation is practiced municipal wastewater consists only of greywater

Greywater

Greywater is wastewater generated from domestic activities such as laundry, dishwashing, and bathing, which can be recycled on-site for uses such as landscape irrigation and constructed wetlands...

, which can be recycled for gardening. However, in most cases greywater continues to be discharged to sewers.

Sanitation and public health

The importance of the isolation of waste lies in an effort to prevent diseases which can be transmitted

Transmission (medicine)

In medicine and biology, transmission is the passing of a communicable disease from an infected host individual or group to a conspecific individual or group, regardless of whether the other individual was previously infected...

through human waste, which afflict both developed countries as well as developing countries to differing degrees. It is estimated that up to 5 million people die each year from preventable water-borne disease, as a result of inadequate sanitation and hygiene practices. The affects of sanitation have also had a large impact on society. The results of studies published in Griffins Public Sanitation show that better sanitation produces an enhanced feeling of wellbeing.

Relevant disease include:

Waterborne diseases
Waterborne diseases
Waterborne diseases are caused by pathogenic microorganisms which are directly transmitted when contaminated fresh water is consumed. Contaminated fresh water, used in the preparation of food, can be the source of foodborne disease through consumption of the same microorganisms...

, which can contaminate drinking water
Diseases transmitted by the fecal-oral route
Fecal-oral route
The fecal-oral route, or alternatively, the oral-fecal route or orofecal route is a route of transmission of diseases, in which they are passed when pathogens in fecal particles from one host are introduced into the oral cavity of another potential host.There are usually intermediate steps,...
Hookwork, where eggs can survive in the soil

Global access to improved sanitation

The Joint Monitoring Program for water and sanitation of WHO

Who

Who may refer to:* Who , an English-language pronoun* who , a Unix command* Who?, one of the Five Ws in journalism- Art and entertainment :* Who? , a 1958 novel by Algis Budrys...

and UNICEF has defined improved sanitation as

connection to a public sewer
Sanitary sewer
A sanitary sewer is a separate underground carriage system specifically for transporting sewage from houses and commercial buildings to treatment or disposal. Sanitary sewers serving industrial areas also carry industrial wastewater...
connection to a septic system
pour-flush
Flush toilet
A flush toilet is a toilet that disposes of human waste by using water to flush it through a drainpipe to another location. Flushing mechanisms are found more often on western toilets , but many squat toilets also are made for automated flushing...

latrine
Latrine
A latrine is a communal facility containing one or more commonly many toilets which may be simple pit toilets or in the case of the United States Armed Forces any toilet including modern flush toilets...
simple pit latrine
ventilated improved pit latrine

According to that definition, 62% of the world's population has access to improved sanitation in 2008, up by 8% since 1990. Only slightly more than half of them or 31% of the world population lived in houses connected to a sewer. Overall, 2.5 billion people lack access to improved sanitation and thus must resort to open defecation or other unsanitary forms of defecation, such as public latrines or open pit latrines. This includes 1.2 billion people who have access to no facilities at all. This outcome presents substantial public health risks as the waste could contaminate drinking water

Drinking water

Drinking water or potable water is water pure enough to be consumed or used with low risk of immediate or long term harm. In most developed countries, the water supplied to households, commerce and industry is all of drinking water standard, even though only a very small proportion is actually...

and cause life threatening forms of diarrhea

Diarrhea

Diarrhea , also spelled diarrhoea, is the condition of having three or more loose or liquid bowel movements per day. It is a common cause of death in developing countries and the second most common cause of infant deaths worldwide. The loss of fluids through diarrhea can cause dehydration and...

to infants. Improved sanitation, including hand washing

Hand washing

and water purification, could save the lives of 1.5 million children who die from diarrheal diseases each year.

In developed countries, where less than 20% of the world population lives, 99% of the population has access to improved sanitation and 81% were connected to sewers.

Solid waste disposal

Disposal of solid waste is most commonly conducted in landfill

Landfill

A landfill site , is a site for the disposal of waste materials by burial and is the oldest form of waste treatment...

s, but incineration, recycling

Recycling

Recycling is processing used materials into new products to prevent waste of potentially useful materials, reduce the consumption of fresh raw materials, reduce energy usage, reduce air pollution and water pollution by reducing the need for "conventional" waste disposal, and lower greenhouse...

, compost

Compost

Compost is organic matter that has been decomposed and recycled as a fertilizer and soil amendment. Compost is a key ingredient in organic farming. At its most essential, the process of composting requires simply piling up waste outdoors and waiting for the materials to break down from anywhere...

ing and conversion to biofuel

Biofuel

Biofuel is a type of fuel whose energy is derived from biological carbon fixation. Biofuels include fuels derived from biomass conversion, as well as solid biomass, liquid fuels and various biogases...

s are also avenues. In the case of landfills, advanced countries typically have rigid protocols for daily cover

Daily cover

Daily cover is the name given to the layer of compressed soil or earth which is laid on top of a day's deposition of waste on an operational landfill site. The cover helps prevent the interaction between the waste and the air, reducing odors and enabling a firm base upon which for vehicles to operate...

with topsoil, where underdeveloped countries customarily rely upon less stringent protocols. The importance of daily cover lies in the reduction of vector contact and spreading of pathogen

Pathogen

A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...

s. Daily cover also minimises odor emissions and reduces windblown litter. Likewise, developed countries typically have requirements for perimeter sealing of the landfill with clay-type soils to minimize migration of leachate

Leachate

Leachate is any liquid that, in passing through matter, extracts solutes, suspended solids or any other component of the material through which it has passed....

that could contaminate groundwater

Groundwater

Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock...

(and hence jeopardize some drinking water

Drinking water

supplies).

For incineration options, the release of air pollutants, including certain toxic components is an attendant adverse outcome. Recycling and biofuel conversion are the sustainable options that generally have superior life cycle costs, particularly when total ecological consequences are considered. Composting value will ultimately be limited by the market demand for compost product.

Sanitation in the developing world

The United Nations

United Nations

The United Nations is an international organization whose stated aims are facilitating cooperation in international law, international security, economic development, social progress, human rights, and achievement of world peace...

Millennium Development Goals

The Millennium Development Goals are eight international development goals that all 193 United Nations member states and at least 23 international organizations have agreed to achieve by the year 2015...

(MDGs) include a target to reduce by half the proportion of people without access to basic sanitation by 2015. In December 2006, the United Nations General Assembly

United Nations General Assembly

For two articles dealing with membership in the General Assembly, see:* General Assembly members* General Assembly observersThe United Nations General Assembly is one of the five principal organs of the United Nations and the only one in which all member nations have equal representation...

declared 2008 'The International Year of Sanitation', in recognition of the slow progress being made towards the MDGs sanitation target. The year aims to develop awareness and action to meet the target. Particular concerns are:

Removing the stigma around sanitation, so that the importance of sanitation can be more easily and publicly discussed.
Highlighting the poverty reduction
Poverty reduction
Poverty is the state of human beings who are poor. That is, they have little or no material means of surviving—little or no food, shelter, clothes, healthcare, education, and other physical means of living and improving one's life....

, health
Health
Health is the level of functional or metabolic efficiency of a living being. In humans, it is the general condition of a person's mind, body and spirit, usually meaning to be free from illness, injury or pain...

and other benefits that flow from better hygiene, household sanitation arrangements and wastewater treatment.

Research from the Overseas Development Institute

Overseas Development Institute

The Overseas Development Institute is one of the leading independent think tanks on international development and humanitarian issues. Based in London, its mission is "to inspire and inform policy and practice which lead to the reduction of poverty, the alleviation of suffering and the achievement...

suggests that sanitation and hygiene promotion needs to be better 'mainstreamed' in development, if the MDG on sanitation is to be met. At present, promotion of sanitation and hygiene is mainly carried out through water institutions. The research argues that there are, in fact, many institutions that should carry out activities to develop better sanitation and hygiene in developing countries. For example, educational institutions can teach on hygiene

Hygiene

, and health institutions can dedicate resources to preventative works (to avoid, for example, outbreaks of cholera

Cholera

Cholera is an infection of the small intestine that is caused by the bacterium Vibrio cholerae. The main symptoms are profuse watery diarrhea and vomiting. Transmission occurs primarily by drinking or eating water or food that has been contaminated by the diarrhea of an infected person or the feces...

).

The Institute of Development Studies

Institute of Development Studies

The Institute of Development Studies based at the University of Sussex is a global organisation for research, teaching and communications on international development....

(IDS) coordinated research programme on Community-led Total Sanitation (CLTS) is a radically different approach to rural sanitation in developing countries and has shown promising successes where traditional rural sanitation programmes have failed. CLTS is an unsubsidized approach to rural sanitation that facilitates communities to recognize the problem of open defecation and take collective action to clean up and become ‘open defecation free’. It uses community-led methods such as participatory mapping and analysing pathways between feces and mouth as a means of galvanizing communities into action. An IDS 'In Focus' Policy Brief suggests that in many countries the Millennium development goal for sanitation is off track and asks how CLTS can be adopted and spread on a large scale in the many countries and regions where open defecation still prevails.

Sanitation in the food industry

Sanitation within the food industry means the adequate treatment of food-contact surfaces by a process that is effective in destroying vegetative cells of microorganism

Microorganism

A microorganism or microbe is a microscopic organism that comprises either a single cell , cell clusters, or no cell at all...

s of public health

Public health

Public health is "the science and art of preventing disease, prolonging life and promoting health through the organized efforts and informed choices of society, organizations, public and private, communities and individuals" . It is concerned with threats to health based on population health...

significance, and in substantially reducing numbers of other undesirable microorganisms, but without adversely affecting the food or its safety for the consumer (U.S. Food and Drug Administration, Code of Federal Regulations

Code of Federal Regulations

The Code of Federal Regulations is the codification of the general and permanent rules and regulations published in the Federal Register by the executive departments and agencies of the Federal Government of the United States.The CFR is published by the Office of the Federal Register, an agency...

, 21CFR110, USA). Sanitation Standard Operating Procedures

Sanitation Standard Operating Procedures

Sanitation Standard Operating Procedures is the common name give to the sanitation procedures in food production plants which are required by the Food Safety and Inspection Service of the USDA and regulated by 9 CFR part 416 in conjunction with 21 CFR part 178.1010...

are mandatory for food industries in US, which are regulated by 9 CFR part 416 in conjunction with 21 CFR part 178.1010. Similarly, in Japan, food hygiene has to be achieved through compliance with food sanitation law.

Additionally, in the food and biopharmaceutical

Biopharmaceutical

Biopharmaceuticals are medical drugs produced using biotechnology. They include proteins , nucleic acids and living microorganisms like virus and bacteria where the virulence of viruses and bacteria is reduced by the process of attenuation, they can be used for therapeutic or in vivo diagnostic...

industries, the term sanitary equipment means equipment that is fully cleanable using clean-in-place

Clean-in-place

Clean-in-Place is a method of cleaning the interior surfaces of pipes, vessels, process equipment, filters and associated fittings, without disassembly....

(CIP) and sterilization-in-place (SIP) procedures: that is fully drainable from cleaning solutions and other liquid

Liquid

Liquid is one of the three classical states of matter . Like a gas, a liquid is able to flow and take the shape of a container. Some liquids resist compression, while others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly...

s. The design should have a minimum amount of deadleg or areas where the turbulence

Turbulence

In fluid dynamics, turbulence or turbulent flow is a flow regime characterized by chaotic and stochastic property changes. This includes low momentum diffusion, high momentum convection, and rapid variation of pressure and velocity in space and time...

during cleaning is insufficient to remove product deposits. In general, to improve cleanability, this equipment is made from Stainless Steel

Stainless steel

In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....

316L, (an alloy

Alloy

An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...

containing small amounts of molybdenum

Molybdenum

Molybdenum , is a Group 6 chemical element with the symbol Mo and atomic number 42. The name is from Neo-Latin Molybdaenum, from Ancient Greek , meaning lead, itself proposed as a loanword from Anatolian Luvian and Lydian languages, since its ores were confused with lead ores...

). The surface is usually electropolished to an effective surface roughness of less than 0.5 micrometre

Micrometre

A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...

to reduce the possibility of bacteria

Bacteria

Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...

l adhesion.

External links

Urban Wastewater Treatment in France, MEEDDM
IRC International Water and Sanitation Centre, the Hague, the Netherlands
http://www.who.int/topics/sanitation/en/
Sanitation, Hygiene and Wastewater Resource Guide (World Bank)
Tilley et al.: Compendium of Sanitation Systems and Technologies, Water Supply and Sanitation Collaborative Council
Water Supply and Sanitation Collaborative Council
The Water Supply and Sanitation Collaborative Council is an international organization whose secretariat in Geneva, Switzerland is hosted by the United Nations Office for Project Services...

/ Swiss Federal Institute of Aquatic Science and Technology (EAWAG), 2008
Central Asia Health Review (CAHR). Poor Sanitation Causes Death among Children under Five in Afghanistan
The 2006 UNDP Human Development Report: Beyond scarcity: Power, poverty and the global water crisis - Chapter 3: The vast deficit in sanitation accessed on August 22, 2007
Water Supply and Sanitation, World Bank accessed on August 22, 2007
Early urban sanitation in ancient India
Sanitation coverage vs. population growth: an encouraging trend
Daily cover in landfills
Hy2U innovative handwashing device and campaign
Your Health in Your Hands UNICEF Documentary narrated by Khaled Abol Naga
Poo Productions, music and film organization raising awareness about sanitation issues
Akvo.org - The open source for water and sanitation, including the Akvopedia, water and sanitation wiki
Community-Led Total Sanitation (CLTS)
India's National Level portal on Sanitation
Google - public data "Improved sanitation facilities, urban (% of urban population with access)"

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