Guwahati, April 22: City architects and electrical engineers want Dispur to make installation of lightning conductors mandatory in all residential buildings.

Construction and safety norms of buildings in the city are decided by the Guwahati development department through the Guwahati Building Construction (Regulation) Byelaws, 2014. These rules are enforced by the GMDA.

"The GMDA bylaws do not make installation of lightning conductors or arresters or, for that matter, any kind of lightning protection system mandatory. The chief electrical engineers of Assam Power Distribution Corporation Limited suggest that while homeowners do check electrical safeties of buildings, there is no such mandatory norm for lightning safety in the city," Pinakpani Chakraborty, a city-based electrical consultant, told The Telegraph.

Lightning conductors or arresters comprise two parts - the conductor, which is made up of the air terminal and bonding conductor, and ground electrodes. Air terminals mainly consist of metal rods that absorb the lightning strikes, the bonding conductors carry the electrical charge to the electrodes set underground and the current is discharged safely without causing any damage to the house or its occupants.

Lightning conductors can be bought locally and assembled.

"The conductor costs around Rs 1,200 and the electrodes cost around Rs 3,000. With installation charges, the lightning protection system can be installed within Rs 5,000. The rate may vary based on the size of the building," Chakraborty said.

"Houses above 15m are more prone to lightning strikes. So lightning protection system becomes essential in those buildings. Also, roofing of the houses needs to be done at least 10m from the ground to safeguard the occupants. The protection system needs to be checked and maintained yearly as the electrodes tend to erode," said Proilkya Bora, additional chief electrical inspector and adviser to the Assam power department.

"Many people are not aware about the protection system while many builders avoid it to save costs. So, it would be better if the electricity department or the GMDA makes installation of a lightning protection system mandatory," Bora said.

Protection from lightning has become a big concern in Assam, especially after six persons were killed and nine injured in lightning strikes in the past two weeks. The weather office has said this year's pre-monsoon weather activity is "likely to have more lightning than usual".

Arup Das, general secretary of the Assam chapter of Indian Institute of Architecture, said, "Lightning protection system should be made mandatory in every highrise. Also, people need to be made aware about this system."

GMDA chairman Dhiren Baruah refused to comment.

The Assam State Disaster Management's guidelines also do not say anything about lightning protection system in houses.