Re-conceptualize standard setting

The field has seen contributions from numerous disciplines, such as psychology, engineering, biomechanics, industrial design, physiology and anthropometry. In essence, it is the study of designing equipment and devices that fit the human body and its cognitive abilities. The two terms "human factors" and "ergonomics" are essentially synonymous.[2][3][4]

The International Ergonomics Association defines ergonomics or human factors as follows:[5]

Ergonomics (or human factors) is the scientific discipline concerned with the understanding of interactions among humans and other elements of a system, and the profession that applies theory, principles, data and methods to design in order to optimize human well-being and overall system performance.

HF&E is employed to fulfill the goals of occupational health and safety and productivity. It is relevant in the design of such things as safe furniture and easy-to-use interfaces to machines and equipment.

Proper ergonomic design is necessary to prevent repetitive strain injuries and other musculoskeletal disorders, which can develop over time and can lead to long-term disability.

Human factors and ergonomics is concerned with the "fit" between the user, equipment and their environments. It takes account of the user's capabilities and limitations in seeking to ensure that tasks, functions, information and the environment suit each user.

To assess the fit between a person and the used technology, human factors specialists or ergonomists consider the job (activity) being done and the demands on the user; the equipment used (its size, shape, and how appropriate it is for the task), and the information used (how it is presented, accessed, and changed). Ergonomics draws on many disciplines in its study of humans and their environments, including anthropometry, biomechanics, mechanical engineering, industrial engineering, industrial design, information design, kinesiology, physiology, cognitive psychology, industrial and organizational psychology, and space psychology.

30. Toxicology • The study of poisonous substances and their effects on humans and other organisms • Toxicologists assess and compare toxic agents, or toxicants, for their toxicity, the degree of harm a substance can inflict. • Environmental toxicology focuses on effects of chemical poisons released into the environment

Types of Toxicants •• Allergens: cause unnecessary immune response • Neurotoxins: damage nervous system • Endocrine disruptors: interfere with hormones

Carcinogens - agents/compounds that will induce cancer in humans.
e.g. benzene, arsenic, inorganic salts of chromium, nickel, beryllium.

Mutagens - agents that affect the cells of the exposed people in such a way that it may cause cancer in the exposed individiual or an undesirable mutation to occur in some later generation.
e.g. radiation, variety of chemical agents that alter the genetic message.

Teratogens - Agents or compounds that a pregnant woman takes into her body that generate defects in the fetus
e.g. Thalidomide, possibly steroids

Fruit and vegetables are an important part of a healthy diet. The natural chemical compounds contain, such as carbohydrates, sugars, proteins and vitamins, which are essential to human growth and health
The natural toxins of plants may also have adverse effects on the health of people who eat the plants. The content of harmful substances can often be influenced through proper handling. For example, some toxins, such as gyromitrin contained in false morels, are water soluble or volatile and will therefore decompose when boiled. In other words, the natural toxic substances contained in foodstuffs can be avoided by choosing and handling the foodstuffs correctly.

· glycoalkaloids, such as solanine in potatoes and tomatine in raw tomatoes

· nitrates in vegetables

· gyromitrin in false morels

· lectins in beans

· coumarin in cinnamon

Both natural and human-made chemicals have the potential to harm humans. Toxic chemicals can occur naturally. For example, rattlesnake poison and botulin are both naturally occurring chemicals that harm humans. Botulin is the toxin which causes food poisoning and is produced by bacteria. Another example of a naturally occuring chemical that is dangerous to humans is radon. Radon is a naturally occurring radioactive gas that enters homes and buildings from the rocks and soil beneath them. Toxic chemicals can also be created by humans, for example, lead-based paints or pesticides such as DDT.

31Most of us have experienced some form of electric “shock,” where electricity causes our body to experience pain or trauma. If we are fortunate, the extent of that experience is limited to tingles or jolts of pain from static electricity buildup discharging through our bodies

Another effect of electric current on the body, perhaps the most significant in terms of hazard, regards the nervous system. By “nervous system” I mean the network of special cells in the body called “nerve cells” or “neurons” which process and conduct the multitude of signals responsible for regulation of many body functions. The brain, spinal cord, and sensory/motor organs in the body function together to allow it to sense, move, respond, think, and remember.

Nerve cells communicate to each other by acting as “transducers:” creating electrical signals (very small voltages and currents) in response to the input of certain chemical compounds called neurotransmitters, and releasing neurotransmitters when stimulated by electrical signals. If electric current of sufficient magnitude is conducted through a living creature (human or otherwise), its effect will be to override the tiny electrical impulses normally generated by the neurons, overloading the nervous system and preventing both reflex and volitional signals from being able to actuate muscles.

32.Vibration induced health conditions progress slowly. In the beginning it starts as a pain. As the vibration exposure continues, the pain may develop into an injury or disease. Pain is the first health condition that is noticed and should be addressed in order to stop the injury.

Vibration-induced white finger (VWF) is the most common condition among the operators of hand-held vibrating tools. Vibration can cause changes in tendons, muscles, bones and joints, and can affect the nervous system. Collectively, these effects are known as Hand-Arm Vibration Syndrome (HAVS). The symptoms of VWF are aggravated when the hands are exposed to cold.

Workers affected by HAVS commonly report:

· attacks of whitening (blanching) of one or more fingers when exposed to cold

· tingling and loss of sensation in the fingers

· loss of light touch

· pain and cold sensations between periodic white finger attacks

· loss of grip strength

· bone cysts in fingers and wrists

33.Characteristic of global problems: demographic, ecological, wars and terrorism, social (drug addiction, alcoholism, AIDS, etc.).

Manifestation of ecological crisis are diverse, are accompanied by numerous dangers to mankind, are fraught with a global ecological disaster. There is a pollution of soil by hazardous substances. Especially dangerous among them – radioactive substances and dioxine. Soils degrade – they lose humus, desertification and a salification. Deficit of fresh water accrues. Pollution of the ocean, surface and underground water hazardous substances, first of all the petrogene amplifies. The phytoplankton – a basis of a food chain at the ocean and an important source of oxygen perishes Atmosphere pollution proceeds, temperature inversions, oxygen hunger in the cities are observed, acid rains drop out. There is a change of global climate, the ozone layer of the atmosphere of Earth Is exhausted. The irreplaceable loss is caused to the planet biosphere, its genofund is impoverished. Degrade, and even many animal species and plants disappear, biological diversity falls. The woods – the most important regulator of environment are reduced. Ecological trouble concerned also circumterraneous space – it is saturated by "space debris" – the fulfilled artificial heavenly bodies. Other global problem – demographic. The most menacing component of this problem is uncontrollable growth of the population of a planet. Uncontrollable growth of the population of a planet conducts to an overpopulation and an acute shortage of limited resources of Earth for providing the increased mass of her inhabitants. In RK this problem while is shown by a return tendency – there is a decrease in population. The demographic problem has two more parties fraught with dangers – intensive aging of the population and growth of number of people of disabled age, population shift. The problem of technogenic danger is generated by quantitative and high-quality growth of world economy. This extensive growth is accompanied by high level, and at times and increase in accident rate in many types of productive activity, has the high social and economic price of accidents and technogenic catastrophes.

34.There are many chemical substances used in the workplace that can be hazardous.I want to highlight one of the chemical substances which influence in high rate to our organisms Its toxicants

TOXICITY is the ability of a substance to produce an unwanted effect when the chemical has reached a sufficient concentration at a certain site in the body.

The more toxic a material is, the smaller the amount of it necessary to be absorbed before harmful effects are caused. The lower the toxicity, the greater the quantity of it necessary to be absorbed. The toxicity of a chemical is generally measured by experiments on animals (quite often rats).

Once a toxic substance has contacted the body it may have either acute (immediate) or chronic (long term) effects.

Example: Spilling acid on your hand will cause immediate harm, i.e. a burn to the skin.Some of the can lead to the death

Exposure to asbestos or tobacco smoke may result in lung cancer after as much as twenty years (this is a long term effect).

Systemic Poisons - the main toxic action includes the production of internal damage
e.g. Hepatotoxic agents - toxic effects produce liver damage. eg. carbon tetrachloride.

e.g. Nephrotoxic agents - toxic effects produce kidney damage eg. some halogenated hydrocarbons

Carcinogens - agents/compounds that will induce cancer in humans.
Mutagens - agents that affect the cells of the exposed people in such a way that it may cause cancer in the exposed individiual or an undesirable mutation to occur in some later generation.
Teratogens - Agents or compounds that a pregnant woman takes into her body that generate defects in the fetus

35.

· Ionizing emissions is a type of energy released by atoms in the form of electromagnetic waves or particles.

· People are exposed to natural sources of ionizing radiation, such as in soil, water, vegetation, and in human-made sources, such as x-rays and medical devices.

· Ionizing emissions has many beneficial applications, including uses in medicine, industry, agriculture and research.

· As the use of ionizing radiation increases, so does the potential for health hazards if not properly used or contained.

· Acute health effects such as skin burns or acute radiation syndrome can occur when doses of radiation exceed certain levels.

· Low doses of ionizing emission can increase the risk of longer term effects such as cancer.

Beyond certain thresholds, radiation can impair the functioning of tissues and/or organs and can produce acute effects such as skin redness, hair loss, radiation burns, or acute radiation syndrome. These effects are more severe at higher doses and higher dose rates. For instance, the dose threshold for acute radiation syndrome is about 1 Sv (1000 mSv).

If the dose is low or delivered over a long period of time (low dose rate), there is greater likelihood for damaged cells to successfully repair themselves. However, long-term effects may still occur if the cell damage is repaired but incorporates errors, transforming an irradiated cell that still retains its capacity for cell division. This transformation may lead to cancer after years or even decades have passed.

36.Radiation is an energy in the form of electromagnetic waves or particulate matter travelling in the air

Radioactivity Elements and atoms . Atoms are concerned of smaller particles referred to as

Protons neutrons electrons Neutron=proton+electron

Ionizing radiation is produced by unstable atoms .Unstable atoms differ from stable atoms because they have an excess of energy or mass or both

Unstable atoms are said to be radioactive . In order to reach stability these atoms give off or emit to excess energy or mass .These emissions are called radiation .

37. Radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium

Ionizing radiation Ionizing (or ionising in British English) radiation is radiation that carries enough energy to free electrons from atoms or molecules, thereby ionizing them. Ionizing radiation is made up of energetic subatomic particles, ions or atoms moving at high speeds (usually greater than 1% of the speed of light), and electromagnetic waves on the high-energy end of the electromagnetic spectrum. Typical ionizing subatomic particles from radioactivity include alpha particles, beta particles and neutrons. Almost all products of radioactive decay are ionizing because the energy of radioactive decay is typically far higher than that required to ionize. Other subatomic ionizing particles which occur naturally are muons, mesons, positrons, neutrons and other particles that constitute the secondary cosmic rays that are produced after primary cosmic rays interact with Earth's atmosphere.^[1][2] Cosmic rays may also produce radioisotopes on Earth (for example, carbon-14), which in turn decay and produce ionizing radiation. Ionizing Radiation Non-ionizing radiation
Non-ionizing (or non-ionising) radiation refers to any type of electromagnetic radiation that does not carry enough energy per quantum (photon energy) to ionize atoms or molecules—that is, to completely remove an electron from an atom or molecule.^[1] Instead of producing charged ions when passing through matter, the electromagnetic radiation has sufficient energy only for excitation, the movement of an electron to a higher energy state. Ionizing radiation which has a higher frequency and shorter wavelength than nonionizing radiation, has many uses but can be a health hazard; exposure to it can cause burns, radiation sickness, cancer and genetic damage. Using ionizing radiation requires elaborate radiological protection measures which in general are not required with nonionizing radiation. Examples: Visible light, is a very narrow range of electromagnetic radiation of a wavelength that is visible to the human eye (about 400–700 nm), or up to 380–750 nm.^[4] More broadly, physicists refer to light as electromagnetic radiation of all wavelengths, whether visible or not.Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light. Like all other electromagnetic waves, they travel at the speed of light. Microwaves are electromagnetic waves with wavelengths ranging from as long as one meter to as short as one millimeter, or equivalently, with frequencies between 300 MHz (0.3 GHz) and 300 GHz. This broad definition includes both UHF and EHF (millimeter waves), and various sources use different boundaries.

Date: 2015-12-24; view: 859