US car cos might have to strengthen their car roofs to hold upto 2.5 times the car weight from the current 1.5 times. According to a study conducted by International Institue of Highway Standards in Virginia, such higher standards could bring down fatalities on a single roll over by 20%. I wonder how strong the cars in india are. The old opel astra we had had a strong roof good enough for my nephews to run over that… but i never allowed them to even press their hands against the roof of my maruti suzuki zen… so strong !!