Electrical Commissioning Checklists

The acceptance testing and subsequent commissioning of is a critical and important step in the start of any electrical system, regardless of the size of the system or project. A lack of experience in handling this process or poor planning and execution can lead to avoidable delays and compromise security of personnel, which can cause potential productivity losses or adversely impact the credibility and reputation of project management function, all of which can have costly financial implications. Acceptance testing and commissioning of electrical systems is an elaborate and tedious process that has to be carried out very diligently and with extreme caution (given the nature of job). To facilitate the above, an electrical commissioning checklist can be used, which is an easily referenced list of to-do activities that can act as a handy and practical tool for ensuring completion of the work, as desired.

Electrical Commissioning Checklists

General Checks

General checks before commissioning a system include ensuring that all related electrical works are complete; staff and all the maintenance personnel are adequately informed and trained in operating and security measures; all fire safety precautions have been taken; and that emergency procedures are well documented and understood by required staff.

Electrical Checks

As regards the electrical appliances and systems deployed, it is prudent to ensure that all required electrical safety guidelines have been followed; that sufficient precautions have been taken to avoid exposing to conducting liquids; all subsystems and appliances operate as expected (are not faulty or have electrical leakage); high voltage equipment is adequately labeled; that all circuit breakers are installed and inspected; and that accessibility is sufficiently restricted but easily available through facilities management when required and as applicable.

Further checks should ascertain that the electrical power leads are protected from strain or physical damage; working areas are free from un-insulated cabling or tripping hazards because of unattended, loose or coiled wiring; and that the power boards have overload protection and proper grounding. Checks on power points should be done for determining that they are easily locatable and not obstructed in any manner; are properly labeled and in good condition; total power load within prescribed limits; that the high current items are not plugged onto power boards (they should rather be directly plugged into power points); and that the permanent appliances have their own dedicated power points.

Outside Checks

Outdoor checks should ensure that safety procedures are in place for working near overhead power lines; that the site is suitable for the electrical system installation and operation; and that only heavy duty power leads are used.

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Effect of Radon on Dogs

Radon is a radioactive inert gas (also referred to as a noble gas) that is colorless, tasteless and odorless. It is found naturally in the environment, and results from the radioactive decay of radium. Radon is one of the densest inert gas, with its most stable isotope being found in the gaseous state under normal conditions. The gas from natural sources can accumulate in confined areas of buildings. It is also present in certain spring waters and hot springs. Radon is considered to be a serious health hazard due to its radioactivity and can significantly contaminate indoor air quality. The gas has been declared as the second most lung cancer causing factor by the United States Environmental Protection Agency.

Effect of Radon on dogs

The main threat from radon is the possibility of inhaling the gas and its radioactive heavy byproducts (Lead, Polonium and Bismuth) that collect in the air, which can potentially cause respiratory disorders. These decay products stick to the cells that line the passage leading to the lungs.

There is also sufficient evidence which suggests that radon and its isotopes has carcinogenic effects on experimental animals, including dogs. Cancer is caused by mutation in a cell’s genes and may be a result of random mutation, genetic, chemical or toxin exposure. When this gas is inhaled in combination with the decay products, cigarette smoke or uranium ore dust, radon causes lung carcinomas like nasal carcinomas, epidermal carcinomas and skin masses (i.e., fibrosarcoma) in dogs of either gender. Dogs exposed to paints, chemicals and urban areas are considered to have higher incidences of cancer. Typical symptoms of dogs that have radon cancer are inappetance (loss of appetite) or anorexia, fever, difficulty in breathing, hacking, abnormal swellings, lameness and coughing.

Dogs who are suffering from cancer do not even show signs of illness, unless the disease gets severe or is in its final stage. The diagnosis for canine cancer is therefore generally made at a very late stage and is not curative as a result. However, if diagnosed (which is based on physical examination, blood test, biopsy, x-ray and/or ultrasound), the treatment includes certain surgeries, radiation therapy, immunotherapy, or chemotherapy. The veterinarian may refer the pet owner to a board certified oncologist (cancer specialist) for further tests.

As a precautionary measure, testing should be done to check the levels of radon in the house. If the house is found sensitive, steps should be taken to lower the concentrations to acceptable levels.

Keywords- Radon, Isotope, Dogs, Radioactive

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Disadvantages of Flow Cytometry

Flow cytometry, a technique that can help characterize microscopic particles such as cells and chromosomes, enables concurrent analysis of the physical and chemical characteristics of thousands of particles per second, and on various different scientific parameters. Fluorescence-activated cell sorting, which is a specialized form of flow cytometry, can also individually sort a heterogeneous mixture of biological cells into two or more streams, based on their fluorescent light scattering properties. Instrumentation based on this concept is an extremely powerful scientific apparatus that is used in research and microbiology labs for the physical sorting of cells. Flow cytometry also finds further application in the diagnosis of health disorders like leukemia (blood cancer).

Disadvantages of flow cytometry technique

There are however some severe limitations in using this scientific technique. Since the resulting data from flow cytometric analysis is at an aggregate level, it is therefore not easy to observe and measure individual cell behavior. Also, as flow cytometry technique requires the passing of these cells through a fluid stream, it restricts the analysis to only cell suspension solutions. For the same reason, solid tissue cells also have to be disaggregated, by treating the intact tissues with an enzyme, so as to release individual cells for further analysis.

Low cell throughput rate

One major disadvantage with the flow cytometer is its low cell throughput rate. Even for high-speed sorters, this is still less than a few thousand cells per second. Many experiments however require very large number of cells. This implies that even high-speed sorters need to run for long durations, which is not only an expensive proposition but may also pose quality issues because the cells sorted from such long runs may no longer be usable in scientific experiments. This problem may be further aggravated when the sorted cells need to be sterile. Although high speed flow cytometers can give sterile cells, but this makes the operation complex and further reduces the throughput.

Requirement of highly trained operators

Since flow cytometer has very sophisticated instrumentation, only skilled and highly trained operators can run it and get any acceptable levels of performance from such an apparatus.

Flow cytometers are expensive

Flow cytometers are expensive instruments to purchase and maintain. A laser flow cytometer, which can only analyze but not sort, costs almost $100,000 while the arc-lamp based cytometers are only marginally cheaper at about $75,000. Flow cytometers with the additional sorting capability can cost almost double of their cheaper versions. Additionally, operating a high speed sort is another recurring expense that typically costs hundreds of dollars for each run.

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Chemicals for Septic Fields

Septic drain fields (also known as leach fields or leach drains) are primarily targeted at cleaning the fluid, which comes out from the septic tank, from impurities and contaminants. Septic fields consist of an arrangement of pipes and pervious material covered under a layer of soil that helps prevent the wastewater in trenches from being exposed to animals and surface leaching. Leach fields are very useful in disposing organic materials which otherwise are catabolized by microbes.

Different types of septic tank chemicals

Typically, there are two kinds of chemical additives that are used in septic drain fields-inorganic chemicals and organic solvents.

Inorganic chemicals

Inorganic chemicals, usually acids (sulfuric acid) or alkalis (caustic hydroxides) are generally employed in septic fields, for opening the clogged drains. Chemicals such as hydrogen peroxide were used to rejuvenate clogged soil absorption system. However, studies now reveal that it excites the soil granules, destroying the soil structure, thereby affecting its permeability.

Additives such as sulfuric acid and caustic hydroxides should not be used to increase the efficiency of the septic system. They are highly corrosive and can be quite damaging in their concentrated forms. They destroy the microbial population in the septic tank and soil absorption systems and can seriously contaminate the groundwater.

Chemicals that hamper excessive anaerobic growth, thus controlling odor, may contain inorganic compounds such as formaldehyde, paraformaldehyde, and zinc sulfate as active ingredients. These chemicals are quite hazardous as they are biocidal (biocide is a chemical substance capable of killing living organisms).

Organic solvents and chemicals

Organic chemicals, often chlorinated hydrocarbons, are known for their ability to break down oils and greases. These solvents and products (primarily include methylene chloride, trichloroethylene, oils, paints, thinners, disinfectants, pesticides or poisons) unfortunately, also pose a threat to beneficial microbes in the septic field. They hamper the wastewater treatment process, pollute the groundwater and also cause a serious public health hazard. The wastewater may also fine solid granules and soap-scums, which further clog the soil absorption system. Homeowners should avoid excessive use of powdered detergents containing non-biodegradable fillers. These products can plug into your septic system, rendering it ineffective.

Conclusion

Recent researches in wastewater treatment and disposal have shown keen interest in this field. While chemicals in septic system can facilitate bio-solid digestion and scum break up, while also enlivening clogged soil absorption system and enhancing settling by coagulation, one does not necessarily need to add any additives to a septic tank.

Further, when sewage starts to collect on the ground surface or the household plumbing system clogs, it is an indication that the septic system has probably failed. Although the failure may be caused by the septic tank, it is generally the septic field that has failed.

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Chemical properties of High Speed Steel

High speed steel (abbreviation: HSS or HS) is a steel grade used in the manufacturing of a variety of machine tools. Since HSS has more suited mechanical properties for tool making (than the various other grades of carbon steel that have been traditionally used), it is considered to be of better quality for this purpose. Further, while HSS displays very high hardness and abrasion resistant characteristics at room temperatures, it does not lose its hardness even at much higher temperatures. Tools made with HSS can therefore cut much faster than those made of other types of steel and this key property also gives high speed steel its name. Infact, high speed steel has been very critical in the way modern metal processing industry has matured in recent years.

Chemical properties of High Speed Steel

Chemical composition

Tool steels such as high speed steel are an alloy containing many elements other than iron, each of which influences their chemical properties. These elements are carbon (0.65 to 0.80%), chromium (3.75 to 4.00%), tungsten (17.25 to 18.75%), and vanadium (0.90 to 1.30%), as well as cobalt and molybdenum and even aluminum. Other elements that may be present in small quantities are manganese (0.10 to 0.40%), silicon (0.20 to 0.40%), nickel (about 0.30%), copper (0.25%), phosphorus (about 0.30%) and sulphur (about 0.30%).

Broadly, high speed steels are classified into two categories – T type (tungsten based) and M type (molybdenum based).

How does the chemical composition influence the mechanical properties?

Influence on a steel grade’s chemical composition in turn affects its mechanical properties as well (such as the strength and hardness, toughness and brittleness, ductility and malleability), and hence is a very important determinant of the variety of applications for which a particular grade can be used. Chemical properties of a steel grade also dictate its anti-corrosive properties.

Carbon increases the strength of the alloy, which helps it resist from getting deformed when load is applied to it. It also increases the hardness of the alloy, although making it less ductile. In turn, presence of chromium in the iron alloy can significantly delay its oxidation (rusting) by forming an anti-corrosive thin layer of chromium oxide, thereby preventing any mechanical or chemical damage to the tool. Molybdenum helps in preventing the alloy from being scarred, although this makes it less malleable and it also cannot be cold worked.

All the grades of High speed steel require strength and hardness characteristics that have to be maintained even at high temperatures (exceeding 600C). This is typically achieved by heat treatment of the alloy.

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Characteristics of Sundew Plant

Sundew, also known as Drosera, is one of the largest genera of insectivorous plants, cosmopolitan and comprises of 188 species. The family is Droceraceae which consists of plants such as venus-fly trap, pitcher plant, cobra lily and butterworts. They are generally found in wet, marshy places and bogs. Unlike today when they are more of an ornamental plant, insectivorous plants were used for medicinal purposes in the olden days.

Sundew plants trap insects like mosquitoes, flies and gnats with the help of sticky, mucilaginous glands that are present on surface of their leaves. They obtain mineral nutrition from these digested insects. They can be grown everywhere- indoors as well as outdoors. They are easy to handle and do not require much care. Drosera, usually a small perennial, is self-fertilizing and derives nutrition from its traps.

Plant characteristics

Leaves and their carnivorous property

The plant derives its name from the term sundew (dewdrops) referring to the shining drops of mucilage which are at the tip of the tentacles of drosera. They are small herbaceous plants, usually perennial, and form upright rosettes of various sizes depending on the species.

Drosera plants are characterized by leafy tentacles which are covered by mucilaginous glands on the laminae of their surface. The trapping mechanism involves two types of glands - stalked glands and sessile glands. While the former lures the insect by secreting sweet sticky mucilage that traps the insect and enzymes such as esterase, protease, phosphatase and peroxidase that digest the released nutrients, the latter works by breaking the nutrients and absorbing them.

Sundews are specialized insectivorous plants that are built in such a manner that despite the fact that they do not have enzymes (especially nitrate reductase which is required for the uptake of earth-bound nitrates); they can derive nutrition from the trapped insects. The plant is touch-sensitive and enfolds its leaves as soon as it comes in contact with the prey; this is known as thigmotropism. Some species can also bend their tentacles or body at varying angles to enhance the contact with the prey.

Root

The root system is not developed and is mainly used for absorbing water from the soil and also anchoring the plant body firmly. The main function of the root, that of absorbing nutrients from the soil, is useless as the minerals are derived from its trapped prey.

Flower and propagation

Like most other carnivorous plants, the floral arrangement of drosera is held at a height from the leaf, with the help of a long, sturdy stem. This type of arrangement ensures proper visibility to the pollinators. The flower generally opens in direct sunlight and also moves with the moving position of the sun. Also, the flower is self-fertile and can pollinate itself by closing the flower and dropping the pollens within it. The plant can be propagated through its leaves, black colored seeds, crown and cuttings from the roots.

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Characteristics of Thermoplastics

Thermoplastics (also referred to as thermo-engineering plastics) are high molecular weight polymers, which become liquid upon heating and glassy solids on cooling. Bonding between molecules of a polymer could be of varying strength, thus resulting in different type of thermoplastics (such as polythenes that have weak vander-wall bonds, or stronger dipole-dipole hydrogen bonds in nylon, or very strong stacked aromatic ring bonds in polystyrene). Thermoplastics are mostly addition polymers (meaning that they are formed by an addition reaction where smaller molecules combine together to form a larger molecule) and are therefore chemically inert, non-biodegradable and difficult to recycle.

Characteristics of Thermoplastics

Molecular Arrangement of Thermoplastics

Thermoplastics can be broadly classified as either being amorphous or semi-crystalline, based on their molecular arrangement.

Amorphous thermoplastics are characterized by their high brittleness and stiffness nature. They are also clear solids in their normal state. However, they can undergo a transformation of their molecular arrangement at high temperatures and on application of stress. Examples of amorphous thermoplastics are polyamideimide, polyethersulphone, polyetherimide, polyarylate, polysulphone, amorphous polyamide, polymethylmethacrylate, polyvinylchloride, acrylonitrile butadiene styrene and polystyrene.

Semi-crystalline solids, on the other hand, only partially exhibit such characterstics, given their partially amorphous state. Examples of semi-crystalline are polyetheretherketone, polytetrafluoroethylene, polyamide 6.6, polyamide 11, polyphenylene sulphide, polyethylene terephthalate, high and low density polyethylene, polyoxymethylene and polypropylene.

Physical properties of Thermoplastics

Specific gravity of various thermoplastics typically varies from about 0.92 for polyybutylene to 1.72 for poly-vinylidene fluoride.

The tensile yield strength (defined as the engineering stress that causes irreversible deformation) of thermoplastics however has a wide variance, with as low as 2.8 (*10^3 psi) for cross-linked polythene, to as high as 8.0 (*10^3 psi) for polyvinyl chlorides.

Thermal conductivity of these polymers can vary from 1.0 to 3.2 (Btu/ (h ft^2 C)).

Specific heat is in the range of 0.22 to 0.55 (kcal/kg C).

Characteristics of Specific Thermoplastics

Acrylonitrile butadiene styrene is a strong thermoplastic that is also resistive to most bases and acids. However, chlorinated hydrocarbons can still corrode or damage this polymer. It is usable only about 71C temperature, and is used in drainage and vent pipes.

Polybutylene and polyethylene (normal as well as cross-linked varieties) are flexible polymers that find their most common application in pressurized water systems. However, while polybutylene doesn’t get affected by extreme water temperatures, polyethylene cannot be used for hot water.

Polypropylene is a light-weight polymer, and can be used till about 82C temperature, while also being highly resistive to most acids, bases and solvents. It’s primary use in laboratory plumbing.

Polyvinyl chloride is also a strong and highly resistive plastic, with the maximum usable temperature being 60C. This finds applications in piping but should be avoided in hot water applications. A variant polymer, chlorinated polyvinyl chloride, can however be used for higher water temperatures (upto 82C).

Polyvinylidene fluoride is an extremely strong and tough thermoplastic, which is also resistant and non-abrasive. It can be used up to temperatures 138C, and its most common application is in laboratory plumbing.

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Ceramic Alloy Materials

Ceramic materials are inorganic, non-metallic solids. They may be crystalline or amorphous in nature, and are prepared by giving appropriate heating and cooling treatment to these materials. Technically, these can be defined as inorganic oxides, non-oxides or particulate materials that are generally crystalline in nature. The most commonly seen ceramic materials are the pottery and bricks that are made from clay, although they have now found many new uses in engineering, semiconductor industry, tooling, ballistic, gas turbine engines, watches, dental implants, synthetic bones and space equipments.

Ceramic Alloy Materials

Ceramics can broadly be classified into oxides, non-oxides and composites.

Oxide Ceramics

Oxide ceramics – such as alumina or zirconia – are resistant to oxidation, do not react chemically, are good electrical and thermal insulators. These are required to be extremely pure and the manufacturing process is therefore elaborate and complex enough to ensure that no impurities that can significantly alter the properties of these ceramics are left behind. Further, heat treatments for these ceramic materials are attuned to give them a specific crystal structure.

Non-oxide Ceramics

Non-oxide ceramics – like carbides, borides, nitrides or silicides – are typically more prone to oxidation, very hard but chemically un-reactive, and also have good thermal and electrical conductivity properties. Manufacturing non-oxide ceramic materials is generally a three step process, where the required non-oxides are firstly prepared, then mixed into a desired powder and finally heat treated in a controlled oxygen-free environment.

Composites

Composites are a combination of oxides and non-oxides, which have been reinforced together using some particulate matter. They are generally tough and are costly to manufacture, while their conductivity and oxidation resistance will vary on the exact composition. It is possible to prepare a wide variety of such composite ceramics (based on what is the combination of oxides, non-oxides, polymers that are reinforced together), with the objective to tune the toughness, hardness or conductivity that is appropriate for a required condition or application.

Some Examples of Ceramic Materials

Ferrite Magnets, classified as ceramics, are inexpensive permanent magnets. They are however very brittle and should therefore not be used in structural applications. They also have a relatively low thermal tolerance and begin to break down around 300C. These are prepared using iron oxide and strontium or barium oxide, compressed together along with some ceramic binder.

BAM is a ceramic material that contains boron, aluminum, magnesium and titanium boride. It is one of the hardest and smoothest known materials, and finds application in all places that require hard materials that are wear resistant and need frictionless environments (such as coatings on moving parts of equipments and machines). It is licensed an Iowa based company, Des Moines.

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Causes of massive stroke

A stroke is a condition where the blood flow to an area of brain is interrupted. The blockage could be because of a blood clot, ruptured artery or a blood vessel. When the brain is deprived of the vital supply of oxygen and glucose (via blood), the brain cells begin to die, subsequently leading to brain damage. The effects of a massive stroke (also called brain attacks and cerebro-vascular accidents) can be devastating and may result in body paralysis, impairment of speech, memory loss, coma or even death. There are two types of massive stroke- ischemic stroke and hemorrhagic stroke. While the former occurs when a clot develops in an artery that supplies blood to the brain, the latter is caused by bleeding inside the brain.

Causes of massive stroke-

Blockage of an artery-

The most common cause of stroke is the blockage of a brain artery by a clot (thrombosis). Generally, blood vessel inside the brain that has already narrowed is most susceptible to getting blocked by a blood clot (thrombus or embolus). The various factors that cause narrowing of the vessel include high blood pressure, higher cholesterol levels, smoking, increasing age and diabetes.

Embolic stroke-

Embolic stroke is caused when either a clot or an atherosclerotic plaque ( deposits of calcium and cholesterol on the inside wall of artery) dislodges and travels through the blood stream, to finally plug in a brain artery (such as occurs in atrial fibrillation). Subsequently, the oxygen and blood flow is hampered leading to embolic stroke.

Cerebral Hemmorhage-

Cerebral hemorrhage (bleeding in the brain tissue because of blood vessel rupture) can result in a stroke due to the loss of oxygen and blood in brain. Also, the condition further aggravates if the brain tissues get swollen (cerebral edema). The cause of most cerebral hemorrhage is hypertension. This is because of the fact that high blood pressure dangerously results in bursting of the small arteries within the brain and therefore increases pressure on the brain. 

Subarachnoid Hemmorhage-

Brain is lined by a membrane known as the arachnoid membrane. In this condition, blood from a blood vessel leackage gets accumulated beneath this membrane. Aneurysm (abnormal blood-filled ballooning of the walls of the artery) is the most common reason of subarachnoid hemorrhage. Hypertension increases the chances of aneurysm attack. Serious neurological consequences can occur if the subarachnoid hemorrhage is not treated on time.

Vasculitis-

Vasculitis is the inflammation of the blood vessels. It is a rare cause of a massive stroke.

Migraine headache-

Migraine or vascular headaches are another rare cause of massive stroke. The mechanism includes narrowing of blood vessels of the brain resulting in decreased blood and oxygen flow to the brain. This can lead to a situation similar to a stroke with paralysis of one side of the body. The symptoms are usually temporary.

Genetic heredity-
Homocystinuria is a rare condition in which levels of homocystine in the body are increased. It is an example of genetic predisposition to stroke.

Keywords- stroke, blood, oxygen, heart, artery, clot, brain

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Black Community Colleges in Georgia

A few community colleges in the USA have taken on the mantle of providing a much needed mentoring, college experience and vocational training to a vast majority of students belonging to Black, Hispanic and other minority communities. Most of these colleges have religious beginnings and had started down South at a time when slavery was prevalent in American society. Although lesser known and little recognized, there are 106 US colleges today that cater to the educational needs of Black communities.

Spelman College

Spelman College, once known as Atlanta Baptist Female Seminary, was established in Atlanta (Georgia) in 1881 as a private, independent liberal arts college. It is part of the largest consortium of Atlanta University Centre and holds the distinction of being America’s first historically black college of higher education for women.

Spread over an area of 9 acres, with 5 buildings, Spelman offers over 25 majors and minors in various streams.

All the students are female, of which 91% are African-American. Spelman offers degrees in Bachelor of Arts (majors include Art, Child Development, Comparative Women's Studies, Drama, Economics, English, French, History, Music, Philosophy, Political Science, Psychology, Religion, Sociology and Anthropology) and Bachelor of Science (majors include Biochemistry, Biology, Chemistry, Computers, Engineering, Mathematics, Environmental Science and Physics).

Morehouse College

Founded in 1867 by William Jefferson White, Morehouse College (initially called Augusta Institute) is one of the finest all-male liberal arts colleges in Atlanta, Georgia. It is a private, not-for-profit; historically black college spread over 61 acres with 3,000 enrollments. Part of the Atlanta University Centre, it is one of the three non-religious men’s colleges in USA.

Morehouse offers 26 majors leading to a Bachelor of Arts or Bachelor of Science degree; through its three academic divisions – Business Administration & Economics, Humanities and Social Sciences and Science & Mathematics.

Clark-Atlanta University

Clark-Atlanta University (CAU) is private, urban institution located in Atlanta, Georgia established in 1988. It was formed by consolidation of Clark College and Atlanta University and is part of the Atlanta University Centre, with a predominance of African-American heritage.

CAU consists of 37 buildings and has a campus area of more than 125 acres, offering courses through its various academic schools such as Arts and Sciences, Business Administration, Education and Social Work.

Albany State University

Albany State University (ASU) was established in 1903 and is a state-supported, historically black University located in Albany, Georgia. The campus sits over an area of 231 acres and offers more than 30 undergraduate degree programmes and 6 advanced liberal arts and professional degrees.

Albany State has a total enrollment of over 4,000. The university has courses organized into four divisions, namely, Arts & Humanities, Business, Education and Science & Health Professions.

Morris Brown College

Morris Brown College, founded by African Methodist Episcopal Church in 1881, is a private, coeducational, liberal arts college located in the Vine City Community of Atlanta, Georgia.

Morris Brown College offers baccalaureate degrees in the general education program, management entrepreneurship and technology program (MET) and organizational management and leadership program.

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Biological monitoring under OSHA

OSHA (abbreviation for ‘Occupational Safety and Health Administration’, and part of the US Department of Labor), has the responsibility of stipulating workplace safety regulations under the framework established by the US Occupational Safety and Health Act of 1970. Under the “Right to Know” legal principle, every American citizen is entitled to know the chemicals and hazardous materials that they may be exposed to in workplace environment; as well as their potential harmful effects and the preventive measures that should be taken. OSHA mandates that this information is easily made available by the employer; through the Hazard Communications Standards 1985. The same legal framework is also now extended to include communities.

OSHA Information Requirements

While chemical composition of hazardous materials is the most easily available information, variety of other information is also relevant to accurately understand and assess the safety and health conditions of a workplace. Other information like the worker injury and illness records, investigation reports of any accidents that may have occurred, claim records of workers, chemical inventories, records of workers’ exposure to such chemicals, inspection reports and job safety analysis papers are also to be maintained under the OSHA mandate.

                                                                                                     

What is Biological Monitoring?

There are three main methods of gathering and monitoring information required under OSHA. This can be through biological monitoring, ambient monitoring or health surveillance. By definition, biological monitoring ascertains the health risks of industrial chemicals by observing an organism’s internal exposure and reaction to these chemicals. Since the primary and ultimate objective of the “Right to Know” principle is to have access to information – so as to take sufficient preventive measures for avoiding health impairments resulting from chemical exposure, not only access to information but active biological measurement technique may also be mandated as a mechanism to closely monitor the health conditions of workers.

Classification of Biological Monitoring Methods

The key basis of biological monitoring is to observe chemical molecules as they get absorbed by the system and eventually affect the target molecules of the organism. Biological monitoring may however be implemented in a variety of ways. It could be done by determining the chemicals and metabolites in the biological media (which could be blood, urine, exhaled air. excreta or even hair and skin). Other methods of monitoring include quantification of non-adverse biological effect or direct measurement of the chemical interaction with the target molecules.

Biologically Monitored Chemicals under OSHA

A variety of industrial and hazardous chemicals and materials are biologically monitored. The most common materials that are monitored are cadmium and lead.

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