SCIENCE TRIBUNE Thursday, April 13, 2000, Chandigarh, India
 

Criminal neglect of safety
by Jagvir Goyal

SAFETY in construction is one area often relegated to the bottom rung of priorities by the builders and the engineers. Irreparable loss of money, manpower and progress may occur whenever a scaffolding fails, a roof collapses or a fatal accident takes place at site of work. Many builders have the experience that once a worker loses his life in an accident at site, the morale of the working force sinks to a new low.

Smart materials
MATERIALS that change shape and size under the influence of an electric or magnetic field are known as active or smart materials. These materials regain their original shape and size when the field is switched off. Smart materials are basically of two types; one type respond to an applied electric field and the other type respond to a magnetic field. The first type, called electroactive materials, are basically insulators and have very high electrical resistance.

Genome research
by Kalyan Ray
IMAGINE a future when hospitals become a thing of the past, medicines become person-specific and gene drugs repair genetic damages at an early stage to prevent the possibility of disease later. This is no fiction but predictions by scientists of things to come a few decades from now.

 
 
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Criminal neglect of safety
by Jagvir Goyal

SAFETY in construction is one area often relegated to the bottom rung of priorities by the builders and the engineers. Irreparable loss of money, manpower and progress may occur whenever a scaffolding fails, a roof collapses or a fatal accident takes place at site of work. Many builders have the experience that once a worker loses his life in an accident at site, the morale of the working force sinks to a new low. The spirit of working and the progress of work never remain the same as have been earlier. Despite this realisation, safety aspect is often ignored. We, the Indians, are habitual of getting shock treatment. Only when some untoward incident occurs, we begin to take safeguards. Till then, we simply sleep.

Findings of the International Labour Organisation reveal that the accident rate among industrial workers is highest in India, touching 4 per 1000 and a major share of it goes to the construction sector. Indian construction industry is highly labour-intensive. Though mechanisation in construction projects is inevitable but machines are being adopted in a very slow manner. The labour is cheap, unorganised, unaware of its rights and mostly struggling to make both ends meet. The builders, therefore, find it convenient and profitable to use manpower than machines.

Builders dread occurrence of an accident at their work-sites. They know that one fatal accident may result in closure of work for a few days and rise of fear among workers who may refuse to work at higher elevations. Not only this, the credibility of the builder may be at stake. He may have to pay a large amount on account of compensation if the workers are not covered under group insurance. Besides, he may have to wriggle out of legal complications arising upon occurrence of the accident. Now certain organisations have begun to ask for “certified accident record” of the builders before allotting works to them. A high incidence may result in disqualification of a builder. An accident may cause so much trouble. Yet, the only “safety measure” the builders take is to keep praying to gods to keep their site free of accidents. No other measures are taken.

It is time that a “Construction Safety Manual” is evolved, made a part of standard tender document in every organisation and strictly enforced by the supervising agency. Some teething troubles may arise in doing so but gradually the safety aspect will become a part and parcel of every site and the builders will not hesitate in making expenditure on this account.

Looking for a concise construction safety manual, various requirements may be summed up and classified in a few categories as under:

Safety measures while handling tools, equipment and machinery:

1. All electric tools must be properly insulated.

2. All winches and hoists shall be provided with magnetic brakes for automatic operation on failure of electricity.

3. No metallic ladders shall be used when high voltage electric wires are passing overhead.

4. Only skilled persons shall be allowed to handle equipment or machinery.

5. All compressed gas cylinders shall be stored in upright position only, with their valve caps in position.

6. All equipment shall be properly earthed.

7. No electric tools shall be used while standing in water without taking proper precautions.

8. All wire ropes shall be thoroughly checked against any broken strands.

9. Flash back arrestors shall be provided on gas cylinders.

10. All machine guards shall be kept in position while the machines are running.

11. No discarded tools, equipment or machinery shall be allowed to use.

12. The scaffoldings and the wooden planks used shall be strong and durable.

Accessories to be provided to the workers :—

1. All workers shall be provided with safety helmets when work at higher elevations is in progress.

2. All workers deployed at higher elevations shall wear safety belts.

3. Protective gloves, shoes and aprons shall be provided to all workers handling electric equipment and chemicals.

4. Ear plugs shall be provided to workers deployed in high noise level locations.

5. Face masks or nose filters shall be worn by workers in areas where obnoxious gases are released by chimneys or chemical plants. Respiratory equipment shall be available for use when required.

6. Safety goggles and shields shall be used by workers engaged in welding work.

7. Gum-boots and torches shall be provided to workers working inside tunnels.

8. Breathing air hoods shall be provided to workers doing sand blasting or spray painting work.

9. Other accessories as suggested by “Safety organisation” with respect to the nature of work shall be provided.

Safety arrangements to be made at site work :—

1. “Men working overhead” signboards shall be placed around structures on which work is in progress at higher elevations.

2. All floor openings in intermediate floors of a building shall be kept covered with gratings. Otherwise temporary protective railings shall be provided.

3. Warning lights (during night) and red flags (during daytime) shall be provided around dangerous areas of working, near ground-level water tanks and near trenches and excavations.

4. Proper railing shall be provided around all working platforms at higher levels.

5. Nylon safety-mesh shall enwrap working platforms of high-rise structures.

6. Sufficient illumination of all working levels and access arrangements shall be ensured.

7. Any spill-over of oil or grease on ladders, stairs or landings shall be cleaned at once.

8. The height of ladders shall be restricted. Too long ladders shall not be allowed. Intermediate platforms shall be provided to give relief to workers going up.

9. All access arrangements shall be inspected by the engineer to be safe and well supported before allowing their use by the workers.

10. Proper bearing shall be provided to the planks and battens used in temporary platforms. No overhangs shall be permitted.

11. All scaffoldings and shuttering shall be well braced and supported. It must be examined and passed by the engineer before allowing pouring of concrete.

12. In “enclosed” working areas such as tunnels, proper ventilation arrangements shall be made.

13. Full arrangements for storage and handling of explosives, radio-active elements and chemicals shall be made.

14. Firefighting equipment shall always be kept ready. Fire extinguishers shall not be allowed to expire.

15. All working platforms shall be kept clear of projecting nails in wooden planks.

Safety measures when work is in progress :—

1. Vertical cuts in excavation, if any, shall be fully braced or shored.

2. All excavated earth shall be stacked away from the cutting edge to avoid its falling over workers and buying them.

3. Site-offices and stores shall be located at a safe distance from the working area. This shall be specially ensured while constructing a high-rise structure.

4. All vehicles shall be parked away from work-site and the excavated area.

5. Periodic checks of wire-ropes, wooden planks, scaffoldings, shuttering, electric wires & cables and access arrangements shall be carried out.

Safety Organisation :—

On major projects, a proper safety organisation should be established that should make concerted efforts to ensure safety. On minor projects or construction sites, Safety engineers should be appointed. They should ensure implementation of above points. In addition, they should see that (i) Medical facilities and First aid is available at site (ii) An ambulance or a vehicle is always available to carry an accident victim to hospital (iii) One or two persons are trained in giving artificial respiration (iv) Accidents are reported at once to the Project-heads. The Safety organisation should celebrate “safety weeks” to create awareness among workers. Safety awards should be instituted. Accident investigations, lodging of claims and payment of compensation should be ensured by this organisation.

Accidents must be declared intolerable. Safety must be assigned priority. As per a recent survey, Indian construction industry employs 3.2 crore people of whom 2.4 crore are workers. No doubt, it is a big force. Making it undergo safety training programmes may not look feasible at this stage but it can certainly be motivated to follow safety rules by holding safety talks from time to time.

Evolving of a “construction safety manual” and its implementation in true sense will ingrain the importance of safety in the mind of everyone concerned. Once this aim is achieved, we shall be able to match our safety-performance with the best in the world.
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How it works
Smart materials

MATERIALS that change shape and size under the influence of an electric or magnetic field are known as active or smart materials. These materials regain their original shape and size when the field is switched off. Smart materials are basically of two types; one type respond to an applied electric field and the other type respond to a magnetic field. The first type, called electroactive materials, are basically insulators and have very high electrical resistance. Second type of smart materials, called magnetoactive materials, are necessarily magnetic in nature. However, only a small fraction of insulators and only a few of the magnetic substances display smartness. Both the electroactive as well as magnetoactive materials have been known for decades. But the change in shape and size of these materials when subjected to an electric/magnetic field was small and that limited the applicability of smart materials. Recent research conducted on smart materials has given rise to better performance, low cost materials. That, in turn, has given a boost to the efforts for finding newer applications of both the electroactive and the magnetoactive materials.

A measure of response of smart materials to an applied field is the change in length divided by the initial length, known as linear strain, and it is often expressed in percentage change in length. An equally relevant measure parameter for thin films of especially electroactive materials is the change in area per unit area expressed in percentage. Up to 1994 actuated strain in electroactive materials like polyurathane was about 4%. Quick developments took place with regard to new electroactive materials and the strain produced in them. Experiments carried on a variety of plastic materials have shown unprecedented amount of both the change in length in linear samples and in area in thin film specimen. In materials commercially known as silicones strains upto 40% have been reported in the last two years. Experiments conducted on a new electroactive acrylic material (VHB 4910 manufactured by 3M company) by Ron Pelrine and coworkers (reported in the February 2000 issue of Science) quote a value for the percentage change in area of 158% and the value for the linear strain is 217%. In simple words it means that area of the thin film made of the new material under an applied electric field increased to two and half times its original value and the length of a fibre of the material more than tripled under the influence of an electric field. In silicones studied with an applied stress in addition to the electric field improved values of area strain of 93% and linear strain of 117% have been obtained by Pelrine group. These results have shattered the standard for electrically induced changes in size. Further the actuation mechanism has been found to have a fast response time. Change in size can be produced one thousand times a second by applying an electric field that changes at that rate.

Electroactive materials stretch farther and generate more pressure than living muscle. Thus these materials may find use in powering prosthetic limbs. Other possible high demanding applications could be in mini-and microrobots, micro air vehicles, disc drives in computers, covering and uncovering or video displays and moving parts in small machines.

Developments in magnetoactive materials have also taken place but the results are not as dramatic. Till 1996 strain of 0.2% could be produced at temperatures below freezing temperature. A new material, a single crystal of NiMnGa, was found to have a strain of 5% under an applied magnetic field at room temperature. This development took place in 1999 and there is an improvement by a factor of 25 but in comparison to strains in electroactive materials the new results in magnetoactive materials do not look impressive. In the next five years it is expected that smart materials shall be standardised and would be made use of in high technology devices.

B.R. Sood
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Genome research
by Kalyan Ray

IMAGINE a future when hospitals become a thing of the past, medicines become person-specific and gene drugs repair genetic damages at an early stage to prevent the possibility of disease later.

This is no fiction but predictions by scientists of things to come a few decades from now.

The era of "predictive personalised medicine" will be ushered in the millennium, courtesy gene research. It would help doctors detect and treat diseases at an early age in life, thereby eliminating the need for medical care later, scientists say.

The time is onset of a disease would be determined well in advance by analysing an individual's genetic make-up and locating and correcting faulty genes so that the disease can be treated before it actually manifests.

The new era will also help doctors prescribe drugs for individuals since it has often been found that the same medicine causes varying reactions in different persons due to genetic variations.

Therapies would be personalised, based on a person's genetic make-up and life-style, as opposed to the existing across-the-board medicine, Partha Majumder, head of the genetics unit at Indian Statistical Institute (ISI), Calcutta pointed out.

The days are also not far away when tiny gene pieces would act as drugs. Healthy genes will replace faulty ones, removing the possibility of hereditary diseases and reducing risk factors for other diseases. Gene therapy, initiated in USA on laboratory scale, will be the order of the day, says Majumder.

According to Samir Brahmachari, director of the Centre for Biochemical Technology (CBT) in Delhi, a new generation of diagnostics and therapeutics for health care is likely to come up using DNA sequencing and polymerase chain reaction (PCR) technologies.

These techniques will help understand the molecular basis of genetic and multi-factorial problems such as cancer, hypertension, asthma, and neurological and psychiatric diseases, he said. Scientists will get a chance of repair the genetic damage responsible for the disease much before the actual disease occur.

The possibility of gene research triumphing over diseases started a decade ago with the launching of the Human Genome Project (HGP) jointly by USA, UK, Japan, France, Germany and China.

The project set a goal of analysing the entire human genome sequence by 2005 to provide an in-depth understanding and possible treatment for more than 6000 genetic diseases as well as to get an insight into the genetic alterations that increase the risk of developing other diseases. In addition the variability in response to pathogens and human behaviour is also likely to be unravelled by this worldwide research endeavour.

The HGP achieved a major breakthrough in December 1999 when scientists deciphered the genetic code in chromosome-22 — one of the two shortest chromosomes in the human genome — which carries genes linked to congenital heart disease, schizophrenia, mental retardation, birth defects and several cancers including leukaemia.

Another 22 chromosomes are waiting in line to be cracked within the next five years to open the way for made-to-order prescriptions tailored for the patient rather than the condition. — PTI
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New products & discoveries

Educational portal

Aptech Limited has launched comprehensive educational portal www.onlinevarsity.com or www. aptchonlinevarsity.com The portal will offer both IT and non IT content courses. Gaba, the market leader in e learning infrastructure, has strategically aligned with Aptech to provide e learning solutions to corporations worldwide.

Citibank e-shopping launched

Citibank has launched Citibank e-shopping at its website www.citibank/com/india. This facility offers customers a unique online shopping environment where their payments are protected through citibank’s secure payment network.

Citibank has tied up with three merchant websites satyamonline.com, rediff.com and fabmart.com which offer some of the most popular online shopping facilities. Citibank customers have the option of shopping in complete safety and confidence with any of these sites for products ranging from music, books and clothings to toys.

Intel launches eDSP

Intel has launched the e business solutions provider (eDSP) programme in India, which aims to bring the e business developers together from India to establish a “best of class” team of e business experts who can advise and integrate leading edge Intel architecture based solutions.

ERP on the net by Mantraonline

www.mantraonline.com has launched Enterprise Resource Planning (CRP) solutions through the internet. A low, cost effective solution for small and medium enterprises, which can be available off the internet from mantra online.

This method avoids the needs for investment in the kind of costly infrastructure involved in traditional CRP solutions.

All a user needs is a PC on which a Java enabled browser can run (netscape version 4.5 or higher or Internet Explorer version 5.0 or higher.

The CRP solutions has 12 models sales, purchase, inventory, finance, costing, human resources, payroll, fixed assets, customer care, shares, production, production planning and equipment maintenance functions of any manufacturing organisation.

Network Asia capital solutions

Japan’s leading provider of outsourced IT solutions, Trane Cosmos, had made founding investment in Hong Kong based NetworkAsia, a newly formed technology invest firm. The firm will invest in internet, e-commerce and software companies across Asia, including India.

NetworkAsia pursues a unique investment model providing value added capital solutions to companies it invests in. These solutions take the form of financial, technical or operating assistance delivered through NeworkAsia’s management and shareholder.

Industrial products portal

Aptech Ltd has built a comprehensive industrial portal www.industrialproductsfind.com, which would enable the manufacturing industry in India to access their counterparts globally to offer their products and services for mutual benefits. This portal brings together a gamut of industrial products, manufacturers, buyers and sellers on a common B2B e-commerce platform through a unique and comprehensive e-marketplace.

The portal combines a database of over 10,000 products. Visitors will be able to search for products and services through keywords and categories. In addition to core content, the site will have news, analysis and features relevant to the vertical segments.

A crucial element is a permanent virtual exhibition of several companies and a powerful “find and buy” facility that will enable online negotiations leading to business being transacted virtually.

Nortel Networks

Nortel Networks has announced the newest product in its small and medium size business solutions portfolios,. the DayStack 820 ISDN router.

The router is a complete small/remote/branch office connectivity solution that enables customers to create a mini Local Area Network via its four 10 Mbps Cthernet ports, share internet access through a single internet account and simultaneously use their ISDN line for both phone and fax service simply by connecting them to the two integrated phone jacks.

R. Suryamurthy and Gaurav Chaudhry
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Science Quiz
by J. P. Garg

1. This US steelmaker invented a method of converting molten iron into steel. But this process later came to be known as Bessemer Process, named after the British engineer Sir Henry Bessemer, who actually patented it in 1856. Can you name the original inventor?

2. What is common about bitter gourd, blackberry (jamun) and brinjal and why have these been in the news recently?

3. According to the latest predictions, about how many years is it likely to take for half of all the earth’s plant and animal species to vanish? About how many years is it likely to take the earth to recover from the extinction of these species?

4. The engines of most petrol driven vehicles contain a device that vaporises and mixes fuel with air in correct proportion for proper combustion and efficient engine performance. What is this device called? By which system is this device being replaced in modern engines?

5. Which acid is present in vinegar which imparts to vinegar its characteristic taste and smell?

6. Although unauthorised use of these organic compounds is illegal, some quacks use these in medicines and some athletes use these to increase their stamina. Which class of compounds, that have serious harmful side-effects, are we talking about?

7. When two suitable different metallic wires or strips are joined in a loop and the two junctions maintained at different temperatures, a current flows through the circuit. Who discovered this effect? What is this type of circuit called?

8. Snails, oysters, mussels, squids, octopus etc are the most highly developed of the unsegmented invertebrates. To which major division of the animal kingdom do they belong?

9. Lecithin is a substance containing fatty acids and choline (an organic compound) and is used as a nervine tonic. In which main animal tissues is it found?

10. QSSC belongs to one of the most controversial branches of physics, one of whose propounders is the popular Indian astronomer J.V. Narlikar. What does QSSC stand for?

Answers

1. William Kelly 2. These are Indian herbs having anti-diabetic properties but have been patented by a US company 3. 100 years; 10 million years 4. Carburettor; Fuel-injection system 5. Ethanoic acid (formerly acetic acid) 6. Steroids 7. German physicist Thomas Johann Seebeck; thermocouple 8. Mollusca 9. Nerves, semen and liver 10. Quasi-steady-state cosmology.

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