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Safety in construction sector is ignored This
Universe Trends |
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Safety in construction sector is ignored
Construction works are dangerous by nature itself. Many risk factors are involved; many agencies are working together whose coordination is important to ensure safety during construction. The complexity of the work, mounting pressures to achieve the targets and most of the labour being illiterate and unaware of safety steps makes it impossible to eliminate accidents during construction. That’s why, all around the world, more people die at construction works than in road accidents. Yet it is quite possible to minimise the number of accidents during construction by taking some effective steps based on actual experience in construction sector. In October, 2004, the biggest ever campaign was launched in Europe to make engineers, builders and workers aware of the importance of safety during construction. Electrocution, falling from heights and getting crushed under machinery were noted to be the three major causes of accidental deaths during construction. In India, the scene is somewhat different. Indian construction industry is still highly labour intensive and use of machinery is considered by the builders as costlier than employing labour which is available at cheap rates due to unemployment and poverty. The reasons behind most of accidents during construction in India are therefore, failure of scaffolds, falling from heights and getting buried in excavated pits due to collapse of improperly cut earth walls. In May last a seminar on safety in construction was organised in Chandigarh when many useful steps to enforce safety in construction and to eliminate fatal accidents were brought out by the engineers. Some of these are: Ensure that all scaffolds are safe. Get them designed rather than leaving them to foreman’s experience. Decide the spacing of verticals, horizontals and braces carefully. Prefer steel scaffolds to wooden scaffolds. Make safe access arrangements. Wherever motor-run passenger cages are used to transfer people to the top of buildings, take special care of wire ropes and the hoists. Maintain them well and allow none to fail. Wherever the height of building crosses 30 metres, provide temporary lightening protection arrangement. Also provide temporary aviation warning light arrangement to send a signal to the aircraft flying overhead. Allow these to remain in position till permanent arrangements are provided in the buildings. Take adequate measures against fire. Keep gas cylinders upright. Train some workers in use of fire extinguishers and other equipment. In multi-storey buildings, make the use of safety helmets and safety belts compulsory and allow no worker to enter the work area unless he wears these. Provide warning signs around the construction area. Let these scream: Men working overhead! Danger, winch area ahead!! Blasting in progress!!! etc. Always keep first aid box at site and keep it updated. Always keep a standby vehicle at site to rush an injured worker to hospital. Those few moments saved are always precious. Always insulate all electric tools and train workers in using insulating gloves and tools. Provide sufficient illumination of work area if work is in progress at night. Provide emergency lights to avoid panic and stampede during power failures in a building under construction. Always stack the excavated earth away from the pit so that it doesn’t make the sides collapse and bury the workers inside. Keep the excavated sides as sloping not vertical. Create safety cells at sites whose exclusive job should be to ensure implementation of safety steps and to keep making site staff aware of the importance of safety. This cell should observe safety weeks and institute safety awards to encourage the workers. Evolve a construction safety manual which should come handy at construction sites. It will save the trouble of referring to so many codes and guidelines lying scattered in different volumes but never available in time. Organisations should enforce yearly safety audit of their sites by internal as well as external agencies. It is quite possible to minimise the number of accidents during construction by taking some effective steps based on actual experience in construction sector. |
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This
Universe
According to Newton’s law of gravitation all particles of matter attract each other. Then how do the galaxies of universe instead of coming together keep moving away
from each other leading to the expansion of the universe? While there are ever emerging problems in truly understanding the behaviour of the universe, this is not one of them. If the stuff comprising the universe is thrown apart with sufficient velocity then it would be moving apart while it is being slowed down. Indeed if the initial velocity is high enough the slowing down might never lead to a situation when the expansion stops. This arises from the fact that the force of gravity decreases as square of the distance. Consider an experiment where we throw a ball away from earth at a speed such that it might escape the gravitation of the earth. This speed is a little over 11 km per second for the earth. Such a ball will continue to move away. The speed at which this happens is called the escape velocity. Water freezes at 0° Celsius. But it runs as usual in pipes even when the temperature in Jalandhar goes down to -2.6° C and in Adampur
to -4° C. Why? If you go down into the ground the temperature does not get so low during a relatively mild winter as in Jalandhar or Adampur. Even when it does get cold it is for a short time during the day. If you use hand pumps for drawing out water or get it from a deep well you find that it feels warm during winter and cool during summer. In places that are much colder and a significant of the pipe supplying municipal water is exposed to the atmosphere the water does freeze in the exposed part. I remember that when I was living in Quetta as a child and the water tap was in the yard outside, early in the morning my father used to tie rags around the pipe, sometimes soaked in kerosene, and set them on fire. This melted the ice in the exposed part of the pipe and then the water started flowing. Why water gets hot when quick lime is mixed with it to make slaked lime? Quick lime is calcium oxide while slaked lime is calcium hydroxide. These two are different chemicals. The hydroxide is one of the products of a chemical reaction between calcium oxide and
water. In most chemical reactions that happen spontaneously energy is released. They are called exothermic reaction. This happens when gas in our stove burns to produce water vapour, carbon dioxide and other chemicals. This also happens when we burn oil, coal or wood. Therefore, release of heat is not surprising thing. The amount depends on the character of molecules interacting. During parties and marriages when we stand near a loud speaker our chest starts beating while windows begin to rattle. What is the cause? Sound is a longitudinal compression wave. This means that it propagates by compressing and decompressing packets of air. Near a high power loud- speaker the amplitude of compression and decompression is high. It is not surprising that such a wave would also try to vibrate our chest cage and every- thing else in the neighborhood. |
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Learn from ants No insult intended to human teachers, but a research team in England says that the first clear demonstration of true teaching among other animals comes from a species without much of a brain-an ant. A variety of animals do things that onlookers learn to copy, but biologists have a stricter definition for true teaching, explains Nigel R. Franks of the University of Bristol in England. First, teachers do a task less efficiently than they would outside the classroom. Second, pupils of a true teacher learn faster than they would by themselves.
Monitoring BP, glucose Convergent Technologies with its headquarters at Frankenberg,
Germany has launched in India. “Elegance Combi CT-X10”, a state-of-the-art and fully integrated blood glucose & blood pressure monitoring system. The system is a combination of advanced Oscillometric Technology and Amperometric Biosensor technologies. The system has been specifically devised keeping in mind the requirements and convenience of the diabetic patients who have to regularly measure their blood pressure besides the glucose monitoring routine.
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