Highly Inflammable

IF you thought cotton was safer than synthetic, think again. Scientists at the Indian Institute of Technology (IIT), Delhi, have dispelled the myth that it is safer to wear cotton saris while cooking and that cotton garments are less prone to fire. After a two-year WHO-sponsored study, they have concluded that cotton saris, in particular, "catch fire easily and the flames engulf the whole body in a matter of seconds" whereas the flames on synthetic saris are "smaller and the whole sari does not catch fire everytime".

This does not mean that synthetics are safer near a fire, but that cotton, too, is highly unsafe. The latest scientific advice is to avoid wearing 'any' loose-fitting clothes as also those made from thin fabric, whenever near an open flame. On the other hand, tight-fit-ting clothes and those made from dense fabrics "catch fire with less difficulty" and burn slower. Therefore, it is hazardous to wear either a sari, salwar kameez or nightie—regardless of the fabric they are made of—while cooking, but shirts and trousers and garments made from khadi and denim are safer.

The study, conducted by Professor Dinesh Mohan, Dr Sunil Kale and K.S. Bawa Bhalla of the institute's Centre for Biomedical Engineering, proves that loose-fitting cotton garments burn "more vigorously", emitting "very large" flames that move rapidly over the fabric which "neither breaks nor falls off during the burning process". In contrast, in synthetics like terrycot and polyester, combustion is less vigorous and flames are always smaller, localised, travel slowly through the fabric and the fabric tends to melt and fall away. 

"We first stumbled upon the finding six or seven years ago while making a film on safety tips for Diwali. For a visual on how synthetics and cotton burn, we dressed a statue in clothes made from these materials and, to our surprise, found that the cotton ones burned faster with large yellow flames while the synthetics emitted smaller, blue flames—exactly the opposite of what we were trying to show. The visual was dropped and we withheld the advice to wear cotton while burning fire crackers. Two years ago we got a WHO grant to study the problem," says Mohan, an authority on accident and transport safety.

A special burn facility was set up at IIT, Delhi, using a hollow dummy filled with de-aerated water and computerised monitoring and data acquisition technology. A series of tests were conducted where the dummy was dressed up in clothes of different commonly worn fabrics (with undergarments, blouse and dupatta ). Each experiment was photographed and video-taped.

The data analysis showed that a cotton sari caught fire in five seconds and the whole garment was engulfed in flames in 30 seconds with temperatures soaring to 200 degrees centigrade.

A polyester sari, on the other hand, took about 20 seconds to catch fire and took 60 seconds to reach 100 degrees centigrade. A terrycot sari, too, took 20 seconds to catch fire and in 20 seconds the lower part of the mannequin recorded 160 degrees centigrade while temperatures around the chest did not go above 100 degrees centigrade, showing that the flames spread slowly. Silk was most volatile and a sari took 5 to 10 seconds to catch fire, generating temperatures between 250 and 300 degrees centigrade in 15 to 20 seconds.

"Regardless of which burns faster, all such loose-flowing clothes are hazardous near an open flame. Someone has to pour water over the victim as quickly as possible to douse the flame. And though thicker and tight-fitting clothes are safer in a kitchen, they cannot save you in an inferno of the kind that occurred in a Manila discotheque recently," cautions Mohan.

The IIT trio claims that the false sense of security about cotton garments stems from western evaluation methods which do not mimic real-life fire situations. The IIT study focuses on Indian fabrics under simulated real-life situations and concludes: "It is recommended that all loose-flowing garments are more hazardous than thicker garments and people should not be advised to wear cotton saris instead of synthetic ones as this gives a false sense of security. It is also recommended that saris, both cotton and synthetic, should be made safer by the use of flame retardant materials."