Design speedbreakers to reduce road mishaps

Chennai: A badly designed speedbreaker would not only annoy drivers and cause damage to vehicles but leads to fatal accidents too.

Tamil Nadu, which records highest number of road accident fatalities in the country, has been witnessing a steady rise in the number of persons killed in road accidents due to speedbreakers over the years.

In the state, the number of persons killed in road accidents due to speedbreakers has gone up to 297 in 2015 from 181 in 2012. In 2013 and 2014, the state saw a rise in fatalities from 231 and 236 respectively.

Badly designed speedbreakers in the state have become a death trap for two-wheelers and three-wheelers. With various agencies including local bodies and highways department involved in the laying of roads in the state, none follows design, curvature and location when constructing speedbreakers.

Noel A. Kanagaraj, a road safety consultant, said that speedbreakers have become death traps for two-wheelers as Indian Road Congressnorms are not followed. “A two-wheeler driver will be thrown off the vehicle if he hit a steeply done speed breaker without any warning signage or flashes,” he said.

Speedbreakers should be laid as per the IRC norms, he said, adding that besides, the motorists should be warned of the speedbreakers ahead with signage and reflectors and thermostatic paint marked over it.

As per the IRC norms, speedbreakers are formed basically by providing a rounded (of 17 metre radius) hump of 3.7 metre width and 0.10 metre height.

This is calculated to reduce the speed of the vehicle to 25kmph. Truck and buses having larger wheel bases may feel greater inconvenience on passage at such humps. To facilitate appreciable and comfortable passage for larger and heavier vehicles (where their proportion is quite high) humps should be modified with 1.5 met re long ramps (1:20) at each edge.

This design will also enable these vehicles to pass the hump at about 25 km/h. The distance between one hump and another can vary from 100 to 120 metres centre to centre.

Pointing to the recent move by the Chennai corporation to standardise speedbreakers in the bus route roads, Raj Cherubal, director of Chennai City Connect, said that it is good initiative and it should be implemented across the city and the state as well.

“When you build a road it should be based on IRC norms whether it is done by highways department or local body. Simply putting tar is not a road. All roads should comply with international standard following all safety measures,” he said.