A hazard is a potential source of
harm
Harm is a moral and legal concept.
Bernard Gert construes harm as any of the following:
* pain
* death
* disability
*mortality
* loss of abil ity or freedom
* loss of pleasure.
Joel Feinberg gives an account of harm as setbacks to intere ...
. Substances, events, or circumstances can constitute hazards when their nature would allow them, even just theoretically, to cause damage to health, life, property, or any other interest of value. The probability of that harm being realized in a specific ''incident'', combined with the magnitude of potential harm, make up its
risk
In simple terms, risk is the possibility of something bad happening. Risk involves uncertainty about the effects/implications of an activity with respect to something that humans value (such as health, well-being, wealth, property or the environme ...
, a term often used synonymously in colloquial speech.
Hazards can be classified in several ways; they can be classified as
natural
Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are p ...
,
anthropogenic
Anthropogenic ("human" + "generating") is an adjective that may refer to:
* Anthropogeny, the study of the origins of humanity
Counterintuitively, anthropogenic may also refer to things that have been generated by humans, as follows:
* Human im ...
,
technological
Technology is the application of knowledge to reach practical goals in a specifiable and reproducible way. The word ''technology'' may also mean the product of such an endeavor. The use of technology is widely prevalent in medicine, science, ...
, or any combination, such as in the case of the natural phenomenon of
wildfire
A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire ...
becoming more common due to
human-made climate change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...
or more harmful due to changes in building practices. A common theme across many forms of hazards in the presence of
stored energy that, when released, can cause damage. The stored energy can occur in many forms: chemical, mechanical, thermal hazards and by the populations that may be affected and the severity of the associated risk. In most cases, a hazard may affect a range of targets and have little or no effect on others.
Identification of hazards assumes that the potential targets are defined, and is the first step in performing a
risk assessment
Broadly speaking, a risk assessment is the combined effort of:
# identifying and analyzing potential (future) events that may negatively impact individuals, assets, and/or the environment (i.e. hazard analysis); and
# making judgments "on the to ...
.
Characteristics
Environmental hazard
An environmental hazard is a substance, state or event which has the potential to threaten the surrounding natural environment or adversely affect people's health, including pollution and natural disasters such as storms and earthquakes. It can i ...
s include long term environmental deterioration such as acidification of soils and build-up of atmospheric carbon dioxide to communal and involuntary social hazards such as
crime
In ordinary language, a crime is an unlawful act punishable by a State (polity), state or other authority. The term ''crime'' does not, in modern criminal law, have any simple and universally accepted definition,Farmer, Lindsay: "Crime, definit ...
and
terrorism
Terrorism, in its broadest sense, is the use of criminal violence to provoke a state of terror or fear, mostly with the intention to achieve political or religious aims. The term is used in this regard primarily to refer to intentional violen ...
to voluntary and personal hazards such as
drug abuse
Substance abuse, also known as drug abuse, is the use of a drug in amounts or by methods which are harmful to the individual or others. It is a form of substance-related disorder. Differing definitions of drug abuse are used in public health, ...
and
mountain climbing
Mountaineering or alpinism, is a set of outdoor activities that involves ascending tall mountains. Mountaineering-related activities include traditional outdoor climbing, skiing, and traversing via ferratas. Indoor climbing, sport climbing, a ...
.
Environmental hazards usually have defined or common characteristics including their tendency to be rapid onset events meaning they occur with a short warning time, they have a clear source of origin which is easily identified, the impact will be swift and losses suffered quickly during or shortly after the onset of the event, risk of exposure is usually involuntary due to location or proximity of people to the hazard and the "disaster occurs with an intensity and scale that justifies an emergency response".
Hazards may be grouped according to their characteristics.
These factors are related to geophysical events, which are not process specific:
# Areal extent of damage zone
# Intensity of impact at a point
# Duration of impact at a point
# Rate of onset of the event
#
Predictability
Predictability is the degree to which a correct prediction or forecast of a system's state can be made, either qualitatively or quantitatively.
Predictability and causality
Causal determinism has a strong relationship with predictability. Perf ...
of the event
Natural hazards
A natural hazard is a natural phenomenon that might have a negative effect on humans and other animals, or the environment. Natural hazard events can be classified into two broad categories: geophysical and biological.
An example of the distinct ...
may be defined as "extreme events that originate in the biosphere, hydrosphere, lithosphere or atmosphere"
or "a potential threat to humans and their welfare"
which include earthquake, landslide, hurricane and tsunamis. Technological and man-made hazards include explosions, the release of toxic materials, episodes of severe
contamination
Contamination is the presence of a constituent, impurity, or some other undesirable element that spoils, corrupts, infects, makes unfit, or makes inferior a material, physical body, natural environment, workplace, etc.
Types of contamination
W ...
, structural collapses, and transportation, construction and manufacturing
accident
An accident is an unintended, normally unwanted event that was not directly caused by humans. The term ''accident'' implies that nobody should be blamed, but the event may have been caused by unrecognized or unaddressed risks. Most researcher ...
s etc. A distinction can also be made between rapid-onset natural hazards, technological hazards, and social hazards, which are described as being of sudden occurrence and relatively short duration, and the consequences of longer-term environmental degradation such as desertification and drought.
In defining hazard Keith Smith argues that what may be defined as the hazard is only a hazard if there is the presence of humans to make it a hazard and that it is otherwise merely an event of interest. In this sense, the environmental conditions we may consider hostile or hazardous can be seen as neutral in that it is our perception, human location and actions which identify resources and hazards within the range of natural events. In this regard, human sensitivity to environmental hazards is a combination of both physical exposure (natural and/or technological events at a location related to their statistical variability) and human vulnerability (about social and economic tolerance of the same location).
Smith states that natural hazards are best seen in an ecological framework to distinguish between natural events as natural hazards. He says, "natural hazards, therefore, result from the conflict of geophysical processes with people and they lie at the interface what has been called the natural events system and the human interface system." He says that "this interpretation of natural hazards gives humans a central role. Firstly through location, because it is only when people and their possessions get in the way of natural processes that hazard exists."
A natural hazard can be considered as a geophysical event when it occurs in extremes and a human factor is involved that may present a risk. In this context, we can see that there may be an acceptable variation of magnitude which can vary from the estimated normal or average range with upper and lower limits or thresholds. In these extremes, the natural occurrence may become an event that presents a risk to the environment or people.
Smith says "most social and economic activities are geared to some expectation of the 'average' conditions. As long as the variation of the environmental element remains fairly close to this expected performance, insignificant damage occurs and the element will be perceived as beneficial. However, when the variability exceeds some threshold beyond the normal band of tolerance, the same variable starts to impose a stress on society and become a hazard."
Thus, above-average wind speeds resulting in a tropical depression or hurricane according to intensity measures on the
Saffir–Simpson scale
The Saffir–Simpson hurricane wind scale (SSHWS) classifies hurricanes—which in the Western Hemisphere are tropical cyclones that exceed the intensities of tropical depressions and tropical storms—into five categories distinguished by ...
will provide an extreme natural event that may be considered a hazard.
Classification
Hazards can be classified as different types in several ways. One of these ways is by specifying the origin of the hazard. One key concept in identifying a hazard is the presence of stored energy that, when released, can cause damage. The stored energy can occur in many forms: chemical, mechanical, thermal, radioactive, electrical, etc. Another class of hazard does not involve the release of stored energy, but the presence of hazardous situations. Examples include confined or limited egress spaces, oxygen-depleted atmospheres, awkward positions, repetitive motions, low-hanging or protruding objects, etc.
Hazards may also be classified as
natural
Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are p ...
,
anthropogenic
Anthropogenic ("human" + "generating") is an adjective that may refer to:
* Anthropogeny, the study of the origins of humanity
Counterintuitively, anthropogenic may also refer to things that have been generated by humans, as follows:
* Human im ...
, or
technological
Technology is the application of knowledge to reach practical goals in a specifiable and reproducible way. The word ''technology'' may also mean the product of such an endeavor. The use of technology is widely prevalent in medicine, science, ...
. They may also be classified as
health
Health, according to the World Health Organization, is "a state of complete physical, mental and social well-being and not merely the absence of disease and infirmity".World Health Organization. (2006)''Constitution of the World Health Organiza ...
or
safety
Safety is the state of being "safe", the condition of being protected from harm or other danger. Safety can also refer to risk management, the control of recognized hazards in order to achieve an acceptable level of risk.
Meanings
There are ...
hazards and by the populations that may be affected and the severity of the associated risk.
In most cases, a hazard may affect a range of targets and have little or no effect on others. Identification of hazards assumes that the potential targets are defined.
Hazards to navigation
A hazard is a potential source of harm. Substances, events, or circumstances can constitute hazards when their nature would allow them, even just theoretically, to cause damage to health, life, property, or any other interest of value. The probabi ...
are another formal classification of hazard. They are usually only hazardous in the context of obstructions to the passage of shipping in their vicinity.
Based on origin
Natural hazards
Natural hazards such as
earthquake
An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from ...
s,
flood
A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrol ...
s, volcanoes and
tsunami
A tsunami ( ; from ja, 津波, lit=harbour wave, ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explo ...
have threatened people, society, the natural environment, and the
built environment
The term built environment refers to human-made conditions and is often used in architecture, landscape architecture, urban planning, public health, sociology, and anthropology, among others. These curated spaces provide the setting for human ac ...
, particularly more vulnerable people, throughout history, and in some cases, on a day-to-day basis. According to the
Red Cross
The International Red Cross and Red Crescent Movement is a Humanitarianism, humanitarian movement with approximately 97 million Volunteering, volunteers, members and staff worldwide. It was founded to protect human life and health, to ensure re ...
, each year 130,000 people are killed, 90,000 are injured and 140 million are affected by unique events known as natural disasters.
Recent policy-oriented work into hazard management began with the work of
Gilbert White
Gilbert White FRS (18 July 1720 – 26 June 1793) was a " parson-naturalist", a pioneering English naturalist, ecologist, and ornithologist. He is best known for his ''Natural History and Antiquities of Selborne''.
Life
White was born on ...
, the first person to study engineering schemes as a means of mitigating flooding in the US. From 1935 to 1967 White and his colleagues led the research into flood defences, and further collaboration on the investigation was undertaken at the University of Chicago.
In December 1989, after several years of preparation, the United Nations General Assembly adopted resolution 44/236 proclaiming the 1990s as the International Decade for Natural Disaster Reduction. The objective of that decade was stated in the annexe of Resolution 44/236 as follows:
"…to reduce through concerted international action, especially in developing countries, the loss of life, property damage
Property damage (or cf. criminal damage in England and Wales) is damage or destruction of real or tangible personal property, caused by negligence, willful destruction, or act of nature.
It is similar to vandalism and arson (destroying propert ...
, and social and economic disruption caused by natural disasters, such as earthquakes, wind-storms, tsunamis, floods, landslide
Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated grade (slope), slope failures, mudflows, and debris flows. Landslides occur in a variety of ...
s, volcanic eruptions, wildfire
A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire ...
, grasshopper
Grasshoppers are a group of insects belonging to the suborder Caelifera. They are among what is possibly the most ancient living group of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago.
Grasshopp ...
and locust infestations, drought
A drought is defined as drier than normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, an ...
and desertification
Desertification is a type of land degradation in drylands in which biological productivity is lost due to natural processes or induced by human activities whereby fertile areas become increasingly arid. It is the spread of arid areas caused by ...
and other calamities of natural origin."
Methods to reduce risk from natural hazards include construction of high-risk facilities away from areas with high risk,
engineering redundancy, emergency reserve funds, purchasing relevant insurance, and the development of operational recovery plans.
Anthropogenic hazards
Hazards due to human behaviour and activity. The social, natural and built environment are not only at risk from geophysical hazards but also from technological hazards including industrial
explosion
An explosion is a rapid expansion in volume associated with an extreme outward release of energy, usually with the generation of high temperatures and release of high-pressure gases. Supersonic explosions created by high explosives are known ...
s, the release of
chemical hazard
A chemical hazard is a (non-biological) substance that has the potential to cause harm to life or health. Chemicals are widely used in the home and in many other places. Exposure to chemicals can cause acute or long-term detrimental health eff ...
s and
major accident hazards (MAHs).
Technological hazards
Hazards due to technology, and therefore a sub-class of
anthropogenic hazard
Anthropogenic hazards are hazards caused by human action or inaction. They are contrasted with natural hazards. Anthropogenic hazards may adversely affect humans, other organisms, biomes, and ecosystems. They can even cause an omnicide. The f ...
s.
Sociological hazards
Hazards due to sociological causes, also a sub-class of anthropogenic hazards. Sociological hazards include
crime
In ordinary language, a crime is an unlawful act punishable by a State (polity), state or other authority. The term ''crime'' does not, in modern criminal law, have any simple and universally accepted definition,Farmer, Lindsay: "Crime, definit ...
,
terrorist threats and
war
War is an intense armed conflict between states, governments, societies, or paramilitary groups such as mercenaries, insurgents, and militias. It is generally characterized by extreme violence, destruction, and mortality, using regular o ...
.
Based on energy source
Biological hazard
Biological hazards, also known as biohazards, originate in
biological
Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary in ...
processes of living organisms and refer to agents that pose a threat to the health of
living organisms
In biology, an organism () is any life, living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy (biology), taxonomy into groups such as Multicellular o ...
, the security of property, or the health of the environment. The term and
its associated symbol may be used as a warning so that those potentially exposed to the substances will know to take precautions. The biohazard symbol was developed in 1966 by Charles Baldwin, an environmental-health engineer working for the
Dow Chemical Company
The Dow Chemical Company, officially Dow Inc., is an American multinational chemical corporation headquartered in Midland, Michigan, United States. The company is among the three largest chemical producers in the world.
Dow manufactures plastic ...
on the containment products.
and is used in the labelling of biological materials that carry a significant health risk, such as viral samples and used
hypodermic needles
A hypodermic needle (from Greek ὑπο- (''hypo-'' = under), and δέρμα (''derma'' = skin)), one of a category of medical tools which enter the skin, called sharps, is a very thin, hollow tube with one sharp tip. It is commonly used w ...
.
Biological hazards include viruses, parasites, bacteria, food, fungi, and foreign toxins. Many specific biological hazards have been identified. For example, the hazards of naturally occurring bacteria such as ''
Escherichia coli
''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Escher ...
'' and ''
Salmonella
''Salmonella'' is a genus of rod-shaped (bacillus) Gram-negative bacteria of the family Enterobacteriaceae. The two species of ''Salmonella'' are ''Salmonella enterica'' and ''Salmonella bongori''. ''S. enterica'' is the type species and is fur ...
'' are well known as disease-causing pathogens, and a variety of measures have been taken to limit human exposure to these
microorganisms
A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in olde ...
through food safety, good personal hygiene, and education. However, the potential for new biological hazards exists through the discovery of new microorganisms and the development of new genetically modified (GM) organisms. The use of new GM organisms is regulated by various governmental agencies. The US
Environmental Protection Agency
A biophysical environment is a biotic and abiotic surrounding of an organism or population, and consequently includes the factors that have an influence in their survival, development, and evolution. A biophysical environment can vary in scale f ...
(EPA) controls GM plants that produce or resist pesticides (i.e.
Bt corn
Genetically modified maize (corn) is a genetically modified crop. Specific maize strains have been genetically engineered to express agriculturally-desirable traits, including resistance to pests and to herbicides. Maize strains with both trait ...
and
Roundup ready crops
Roundup Ready is the Monsanto trademark for its patented line of genetically modified crop seeds that are resistant to its glyphosate-based herbicide, Roundup (herbicide), Roundup.
History
In 1996, genetically modified ''Roundup Ready'' soybeans r ...
). The US
Food and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...
(FDA) regulates GM plants that will be used as food or for medicinal purposes.
Biological hazards can include medical waste or samples of a
microorganism
A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in olde ...
,
virus
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea.
Since Dmitri Ivanovsky's 1 ...
or
toxin
A toxin is a naturally occurring organic poison produced by metabolic activities of living cells or organisms. Toxins occur especially as a protein or conjugated protein. The term toxin was first used by organic chemist Ludwig Brieger (1849– ...
(from a biological source) that can affect
health
Health, according to the World Health Organization, is "a state of complete physical, mental and social well-being and not merely the absence of disease and infirmity".World Health Organization. (2006)''Constitution of the World Health Organiza ...
. Many biological hazards are associated with food, including certain
virus
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea.
Since Dmitri Ivanovsky's 1 ...
es,
parasite
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...
s,
fungi
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...
,
bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...
, and plant and seafood
toxin
A toxin is a naturally occurring organic poison produced by metabolic activities of living cells or organisms. Toxins occur especially as a protein or conjugated protein. The term toxin was first used by organic chemist Ludwig Brieger (1849– ...
s.
Pathogenic ''
Campylobacter
''Campylobacter'' (meaning "curved bacteria") is a genus of Gram-negative bacteria. ''Campylobacter'' typically appear comma- or s-shaped, and are motile. Some ''Campylobacter'' species can infect humans, sometimes causing campylobacteriosis, a d ...
'' and ''
Salmonella
''Salmonella'' is a genus of rod-shaped (bacillus) Gram-negative bacteria of the family Enterobacteriaceae. The two species of ''Salmonella'' are ''Salmonella enterica'' and ''Salmonella bongori''. ''S. enterica'' is the type species and is fur ...
'' are common foodborne biological hazards. The hazards from these bacteria can be avoided through risk mitigation steps such as proper handling,
storing, and
cooking
Cooking, cookery, or culinary arts is the art, science and craft of using heat to Outline of food preparation, prepare food for consumption. Cooking techniques and ingredients vary widely, from grilling food over an open fire to using electric ...
of food.
Disease in humans can come from biological hazards in the form of infection by bacteria, antigens, viruses, or parasites.
Chemical hazard
A chemical can be considered a hazard if by its intrinsic properties it can cause harm or danger to humans, property, or the environment.
Health hazards associated with chemicals are dependent on the dose or amount of the chemical. For example, iodine in the form of potassium iodate is used to produce
iodised salt
Iodised salt ( also spelled iodized salt) is table salt mixed with a minute amount of various salts of the element iodine. The ingestion of iodine prevents iodine deficiency. Worldwide, iodine deficiency affects about two billion people and is t ...
. When applied at a rate of 20 mg of potassium iodate per 1000 mg of table salt, the chemical is beneficial in preventing
goitre
A goitre, or goiter, is a swelling in the neck resulting from an enlarged thyroid gland. A goitre can be associated with a thyroid that is not functioning properly.
Worldwide, over 90% of goitre cases are caused by iodine deficiency. The term is ...
, while
iodine
Iodine is a chemical element with the symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , and boils to a vi ...
intakes of 1200–9500 mg in one dose has been known to cause death.
Some chemicals have a cumulative biological effect, while others are metabolically eliminated over time. Other chemical hazards may depend on concentration or total quantity for their effects.
A variety of
chemical hazard
A chemical hazard is a (non-biological) substance that has the potential to cause harm to life or health. Chemicals are widely used in the home and in many other places. Exposure to chemicals can cause acute or long-term detrimental health eff ...
s (e.g.
DDT
Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. ...
,
atrazine
Atrazine is a chlorinated herbicide of the triazine class. It is used to prevent pre-emergence broadleaf weeds in crops such as maize (corn), soybean and sugarcane and on turf, such as golf courses and residential lawns. Atrazine's primary manufa ...
, etc.) have been identified. However, every year companies produce more new chemicals to fill new needs or to take the place of older, less effective chemicals. Laws, such as the
Federal Food, Drug, and Cosmetic Act
The United States Federal Food, Drug, and Cosmetic Act (abbreviated as FFDCA, FDCA, or FD&C) is a set of laws passed by the United States Congress in 1938 giving authority to the U.S. Food and Drug Administration (FDA) to oversee the safety of f ...
and the
Toxic Substances Control Act
The Toxic Substances Control Act (TSCA) is a United States law, passed by the 94th United States Congress in 1976 and administered by the United States Environmental Protection Agency (EPA), that regulates chemicals not regulated by other U.S. ...
in the US, require protection of human health and the environment for any new chemical introduced. In the US, the EPA regulates new chemicals that may have environmental impacts (i.e.,
pesticide
Pesticides are substances that are meant to control pests. This includes herbicide, insecticide, nematicide, molluscicide, piscicide, avicide, rodenticide, bactericide, insect repellent, animal repellent, microbicide, fungicide, and lampri ...
s or chemicals released during a manufacturing process), while the FDA regulates new chemicals used in foods or as drugs. The potential hazards of these chemicals can be identified by performing a variety of tests before the authorization of usage. The number of tests required and the extent to which the chemicals are tested varies, depending on the desired usage of the chemical. Chemicals designed as new drugs must undergo more rigorous tests than those used as pesticides.
Some harmful chemicals occur naturally in certain geological formations, such as
radon gas
Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colourless, odourless, tasteless noble gas. It occurs naturally in minute quantities as an intermediate step in the normal radioactive decay chains through ...
or
arsenic
Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, but ...
. Other chemicals include products with commercial uses, such as agricultural and industrial chemicals, as well as products developed for home use. Pesticides, which are normally used to control unwanted insects and plants, may cause a variety of negative effects on non-target organisms.
DDT
Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. ...
can build up, or bioaccumulate, in birds, resulting in thinner-than-normal eggshells, which can break in the nest.
The organochlorine pesticide
dieldrin
Dieldrin is an organochloride originally produced in 1948 by J. Hyman & Co, Denver, as an insecticide. Dieldrin is closely related to aldrin, which reacts further to form dieldrin. Aldrin is not toxic to insects; it is oxidized in the insect to fo ...
has been linked to
Parkinson's disease
Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...
.
Corrosive chemicals like
sulfuric acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formu ...
, which is found in car batteries and research laboratories, can cause severe skin burns. Many other chemicals used in industrial and laboratory settings can cause respiratory, digestive, or
nervous system
In biology, the nervous system is the highly complex part of an animal that coordinates its actions and sensory information by transmitting signals to and from different parts of its body. The nervous system detects environmental changes th ...
problems if they are inhaled, ingested, or absorbed through the skin. The negative effects of other chemicals, such as
alcohol
Alcohol most commonly refers to:
* Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom
* Alcohol (drug), an intoxicant found in alcoholic drinks
Alcohol may also refer to:
Chemicals
* Ethanol, one of sev ...
and
nicotine
Nicotine is a natural product, naturally produced alkaloid in the nightshade family of plants (most predominantly in tobacco and ''Duboisia hopwoodii'') and is widely used recreational drug use, recreationally as a stimulant and anxiolytic. As ...
, have been well documented.
Ergonomic hazard
Ergonomic hazards are physical conditions that may pose a risk of injury to the
musculoskeletal system
The human musculoskeletal system (also known as the human locomotor system, and previously the activity system) is an organ system that gives humans the ability to move using their muscular and skeletal systems. The musculoskeletal system provid ...
, such as the
muscle
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...
s or
ligament
A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Other ligaments in the body include the:
* Peritoneal li ...
s of the lower back,
tendon
A tendon or sinew is a tough, high-tensile-strength band of dense fibrous connective tissue that connects muscle to bone. It is able to transmit the mechanical forces of muscle contraction to the skeletal system without sacrificing its ability ...
s or
nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system.
A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the e ...
s of the hands/wrists, or bones surrounding the knees.
Ergonomic
Human factors and ergonomics (commonly referred to as human factors) is the application of psychological and physiological principles to the engineering and design of products, processes, and systems. Four primary goals of human factors learnin ...
hazards include things such as awkward or extreme postures, whole-body or hand/arm
vibration
Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. The word comes from Latin ''vibrationem'' ("shaking, brandishing"). The oscillations may be periodic function, periodic, such as the motion of a pendulum ...
, poorly designed tools, equipment, or workstations,
repetitive motion, and poor
lighting
Lighting or illumination is the deliberate use of light to achieve practical or aesthetic effects. Lighting includes the use of both artificial light sources like lamps and light fixtures, as well as natural illumination by capturing daylig ...
. Ergonomic hazards occur in both occupational and non-occupational settings such as in workshops, building sites, offices, home, school, or public spaces and facilities.
Mechanical hazard
A mechanical hazard is any hazard involving a machine or industrial process. Motor vehicles, aircraft, and
air bag
An airbag is a vehicle occupant-restraint system using a bag designed to inflate extremely quickly, then quickly deflate during a Traffic collision, collision. It consists of the airbag cushion, a flexible fabric bag, an inflation module, and a ...
s pose mechanical hazards.
Compressed gas
A compressed fluid (also called a compressed or unsaturated liquid, subcooled fluid or liquid) is a fluid under mechanical or thermodynamic conditions that force it to be a liquid.
At a given pressure, a fluid is a compressed fluid if it is at ...
es or liquids can also be considered a mechanical hazard.
Hazard identification of new machines and/or industrial processes occurs at various stages in the design of the new machine or process. These hazard identification studies focus mainly on deviations from the intended use or design and the harm that may occur as a result of these deviations. These studies are regulated by various agencies such as 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 agenc ...
and the
National Highway Traffic Safety Administration
The National Highway Traffic Safety Administration (NHTSA ) is an agency of the U.S. federal government, part of the Department of Transportation. It describes its mission as "Save lives, prevent injuries, reduce vehicle-related crashes" rela ...
.
Physical hazard
A physical hazard is a naturally occurring process that has the potential to create loss or damage. Physical hazards include
earthquakes
An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from ...
,
floods
A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrolog ...
,
fire
Fire is the rapid oxidation of a material (the fuel) in the exothermic chemical process of combustion, releasing heat, light, and various reaction Product (chemistry), products.
At a certain point in the combustion reaction, called the ignition ...
s, and
tornado
A tornado is a violently rotating column of air that is in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, altho ...
es. Physical hazards often have both human and natural elements. Flood problems can be affected by the natural elements of climate fluctuations and storm frequency, and by land drainage and building in a
flood plain
A floodplain or flood plain or bottomlands is an area of land adjacent to a river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge.Goudi ...
, human elements.
Another physical hazard,
X-rays
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 Picometre, picometers to 10 Nanometre, nanometers, corresponding to frequency, ...
, naturally occur from
solar radiation
Solar irradiance is the power per unit area (surface power density) received from the Sun in the form of electromagnetic radiation in the wavelength range of the measuring instrument.
Solar irradiance is measured in watts per square metre (W/m ...
, but have also been utilized by humans for medical purposes; however,
overexposure
In photography, exposure is the amount of light per unit area (the image plane's illuminance times the exposure time) reaching a frame of photographic film or the surface of an electronic image sensor, as determined by shutter speed, lens F-n ...
can lead to
cancer
Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...
,
skin burn
A burn is an injury to skin, or other tissues, caused by heat, cold, electricity, chemicals, friction, or ultraviolet radiation (like sunburn). Most burns are due to heat from hot liquids (called scalding), solids, or fire. Burns occur mai ...
s, and
tissue damage.
Psychosocial hazard
Psychological or psychosocial hazards are hazards that affect the psychological well-being of people, including their ability to participate in a work environment among other people. Psychosocial hazards are related to the way work is designed, organized, and managed, as well as the economic and social contexts of work, and are associated with psychiatric, psychological, and/or physical injury or illness. Linked to psychosocial risks are issues such as occupational stress and workplace violence, which are recognized internationally as major challenges to occupational health and safety.
Based on effects
Health hazards
Hazards that would affect the health of exposed persons, usually having an acute or chronic illness as the consequence. Fatality would not normally be an immediate consequence. Health hazards may cause measurable changes in the body which are generally indicated by the development of signs and symptoms in the exposed persons, or non-measurable, subjective symptoms.
Safety hazards
Hazards that would affect the safety of individuals, usually having an injury or immediate fatality as the consequence of an incident.
Economic hazards
Hazards that would affect property, wealth and the economy.
Environmental hazards
Any single or combination of toxic chemical, biological, or physical agents in the environment, resulting from human activities or natural processes, that may affect the health of exposed subjects, including pollutants such as heavy metals, pesticides, biological contaminants, toxic waste, and industrial and home chemicals
Hazards that would affect the environment, particularly the natural environment and ecosystems.
Disasters
Disaster
A disaster is a serious problem occurring over a short or long period of time that causes widespread human, material, economic or environmental loss which exceeds the ability of the affected community or society to cope using its own resources ...
can be defined as a serious disruption, occurring over a relatively short time, of the functioning of a community or a society involving widespread human, material, economic, societal or
environmental loss and impacts, which exceeds the ability of the affected community or society to cope using its own resources.
Disaster can manifest in various forms, threatening those people or environments specifically vulnerable. Such impacts include loss of property, death, injury, trauma or
post-traumatic stress disorder
Post-traumatic stress disorder (PTSD) is a mental and behavioral disorder that can develop because of exposure to a traumatic event, such as sexual assault, warfare, traffic collisions, child abuse, domestic violence, or other threats on ...
.
Disaster can take various forms, including hurricane,
volcano
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
On Earth, volcanoes are most often found where tectonic plates are ...
, tsunami, earthquake,
drought
A drought is defined as drier than normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, an ...
,
famine
A famine is a widespread scarcity of food, caused by several factors including war, natural disasters, crop failure, Demographic trap, population imbalance, widespread poverty, an Financial crisis, economic catastrophe or government policies. Th ...
,
plague
Plague or The Plague may refer to:
Agriculture, fauna, and medicine
*Plague (disease), a disease caused by ''Yersinia pestis''
* An epidemic of infectious disease (medical or agricultural)
* A pandemic caused by such a disease
* A swarm of pes ...
, disease,
rail crash,
car crash,
tornado
A tornado is a violently rotating column of air that is in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, altho ...
,
deforestation
Deforestation or forest clearance is the removal of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. The most concentrated d ...
, flooding, toxic release, and spills (
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 ...
,
chemicals
A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., wit ...
). These can affect people and the environment on the local regional level, national level or international level (Wisner et al., unknown) where the international community becomes involved with aid donation, governments give money to support affected countries' economies with disaster response and post-disaster reconstruction.
A disaster hazard is an extreme geophysical event that is capable of causing a disaster. 'Extreme' in this case means a substantial variation in either the positive or the negative direction from the normal trend; flood disasters can result from exceptionally high precipitation and river discharge, and drought is caused by exceptionally low values.
The fundamental determinants of hazard and the risk of such hazards occurring is timing, location, magnitude and frequency.
For example, magnitudes of earthquakes are measured on the Richter scale from 1 to 10, whereby each increment of 1 indicates a tenfold increase in severity. The magnitude-frequency rule states that over a significant period of time many small events and a few large ones will occur.
Hurricanes and typhoons on the other hand occur between 5 degrees and 25 degrees north and south of the equator, tending to be seasonal phenomena that are thus largely recurrent in time and predictable in location due to the specific climate variables necessary for their formation.
Major disaster, as it is usually assessed on quantitative criteria of death and damage, was defined by Sheehan and Hewitt (1969),
having to conform to the following criteria:
* At least 100 people dead,
* at least 100 people injured, or
* at least $1 million damage
This definition includes indirect losses of life caused after the initial onset of the disaster such as secondary effects of, e.g., cholera or dysentery. This definition is still commonly used but has the limitations of number of deaths, injuries, and damage (in $).
UNDRO (1984) defined a disaster in a more qualitative fashion as:
an event, concentrated in time and space, in which a community undergoes severe danger and incurs such losses to its members and physical appurtenances that the social structure is disrupted and the fulfilment of all or some of the essential functions of the society is prevented.
As with other definitions of disaster, this definition not only encompasses the social aspect of disaster impact and stresses potentially caused but also focuses on losses, implying the need for emergency response as an aspect of the disaster.
It does not, however, set out quantitative thresholds or scales for damage, death, or injury, respectively.
Status of a hazard
![Ukraine road sign 3](https://upload.wikimedia.org/wikipedia/commons/e/e8/Ukraine_road_sign_3.43.gif)
Hazards are sometimes classified into three modes or statuses:
* Dormant—The situation environment is currently affected. For instance, a hillside may be unstable, with the potential for a
landslide
Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated grade (slope), slope failures, mudflows, and debris flows. Landslides occur in a variety of ...
, but there is nothing below or on the hillside that could be affected.
* Armed—People, property, or environment are in potential harm's way.
* Active—A harmful incident involving the hazard has actually occurred. Often this is referred to not as an "active hazard" but as an
accident
An accident is an unintended, normally unwanted event that was not directly caused by humans. The term ''accident'' implies that nobody should be blamed, but the event may have been caused by unrecognized or unaddressed risks. Most researcher ...
,
emergency
An emergency is an urgent, unexpected, and usually dangerous situation that poses an immediate risk to health, life, property, or environment and requires immediate action. Most emergencies require urgent intervention to prevent a worsening ...
, incident, or
disaster
A disaster is a serious problem occurring over a short or long period of time that causes widespread human, material, economic or environmental loss which exceeds the ability of the affected community or society to cope using its own resources ...
.
Risk
The terms "hazard" and "
risk
In simple terms, risk is the possibility of something bad happening. Risk involves uncertainty about the effects/implications of an activity with respect to something that humans value (such as health, well-being, wealth, property or the environme ...
" are often used interchangeably. However, in terms of risk assessment, these are two very distinct terms. A hazard is an agent that can cause harm or damage to humans, property, or the environment.
Risk is the probability that exposure to a hazard will lead to a negative consequence, or more simply, a hazard poses no risk if there is no exposure to that hazard.
Risk
In simple terms, risk is the possibility of something bad happening. Risk involves uncertainty about the effects/implications of an activity with respect to something that humans value (such as health, well-being, wealth, property or the environme ...
can be defined as the
likelihood
The likelihood function (often simply called the likelihood) represents the probability of random variable realizations conditional on particular values of the statistical parameters. Thus, when evaluated on a given sample, the likelihood funct ...
or probability of a given hazard of a given level causing a particular level of loss of damage. The elements of risk are populations, communities, the
built environment
The term built environment refers to human-made conditions and is often used in architecture, landscape architecture, urban planning, public health, sociology, and anthropology, among others. These curated spaces provide the setting for human ac ...
, the
natural environment
The natural environment or natural world encompasses all life, living and non-living things occurring nature, naturally, meaning in this case not Artificiality, artificial. The term is most often applied to the Earth or some parts of Earth. Th ...
, economic activities and services which are under threat of
disaster
A disaster is a serious problem occurring over a short or long period of time that causes widespread human, material, economic or environmental loss which exceeds the ability of the affected community or society to cope using its own resources ...
in a given area.
The total risk according to UNDRO 1982 is the "sum of predictable deaths, injuries, destruction, damage, disruption, and costs of repair and mitigation caused by a disaster of a particular level in a given area or areas".
David Alexander
distinguishes between risk and
vulnerability
Vulnerability refers to "the quality or state of being exposed to the possibility of being attacked or harmed, either physically or emotionally."
A window of vulnerability (WOV) is a time frame within which defensive measures are diminished, com ...
, saying that "vulnerability refers to the potential for
casualty
Casualty may refer to:
*Casualty (person), a person who is killed or rendered unfit for service in a war or natural disaster
**Civilian casualty, a non-combatant killed or injured in warfare
* The emergency department of a hospital, also known as ...
, destruction, damage, disruption or other forms of loss in a particular element: risk combines this with the probable level of loss to be expected from a predictable magnitude of hazard (which can be considered as the manifestation of the agent that produces the loss)." Since hazards have varying degrees of severity, the more intense or severe the hazard, the greater vulnerability there will be since the potential for damage and destruction is increased for the severity of the hazard. Ben Wisner argues that risk or disaster is "a compound function of the natural hazard and the number of people, characterised by their varying degrees of vulnerability to that specific hazard, who occupy the space and time of exposure to the hazard event." (Wisner, et al., 1994).
Another definition of risk is "the probable frequency and probable magnitude of future losses". This definition also focuses on the probability of future loss whereby the degree of vulnerability to hazard represents the level of risk on a particular population or environment. The threats posed by a hazard are:
# Hazards to people – death, injury, disease and stress
# Hazards to goods – property damage and economic loss
# Hazards to environment –loss of flora and fauna, pollution and loss of amenity
Marking of hazards
Hazard symbols or warning symbols are easily recognizable
symbol
A symbol is a mark, sign, or word that indicates, signifies, or is understood as representing an idea, object, or relationship. Symbols allow people to go beyond what is known or seen by creating linkages between otherwise very different conc ...
s designed to warn about hazardous materials, locations, or objects. The use of hazard symbols is often regulated by law and directed by
standards organization
A standards organization, standards body, standards developing organization (SDO), or standards setting organization (SSO) is an organization whose primary function is developing, coordinating, promulgating, revising, amending, reissuing, interpr ...
s. Hazard symbols may appear with different colours, backgrounds, borders and supplemental information to specify the type of hazard and the level of threat (for example,
toxicity classes). Warning symbols are used in many places in place of or in addition to written warnings as they are quickly recognized (faster than reading a written warning) and more universally understood, as the same symbol can be recognized as having the same meaning to speakers of different languages.
Navigational hazard
Navigation is a field of study that focuses on the process of monitoring and controlling the motion, movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navi ...
s are generally marked on
nautical chart
A nautical chart is a graphic representation of a sea area and adjacent coastal regions. Depending on the scale of the chart, it may show depths of water and heights of land (topographic map), natural features of the seabed, details of the coa ...
s, and are also often marked by
moored
A mooring is any permanent structure to which a vessel may be secured. Examples include quays, wharfs, jetties, piers, anchor buoys, and mooring buoys. A ship is secured to a mooring to forestall free movement of the ship on the water. An ''an ...
buoy
A buoy () is a floating device that can have many purposes. It can be anchored (stationary) or allowed to drift with ocean currents.
Types
Navigational buoys
* Race course marker buoys are used for buoy racing, the most prevalent form of yac ...
s, and changes are published in
notices to mariners
A notice to mariners (NTM or NOTMAR,) advises sailor, mariners of important matters affecting navigational safety, including new Hydrography, hydrographic information, changes in channel (geography), channels and aids to navigation, and other impo ...
.
See also
*
*
*
*
*
*
*
*
References
External links
*
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