Hong Kong’s double-decker trams will tiptoe through busy neighbourhoods and spare residents the usual screeching when upgrades to the tracks are completed over the next three years. Affectionately nicknamed “ding dings” by locals for their bell sound, the trams generate a less desirable noise when they negotiate sharp bends or junctions. Operator Hong Kong Tramways said work was now under way to replace the noisiest sections of the tracks with a design that was 16 decibels quieter. “Don’t underestimate this number – for every two decibels we reduce, it translates to a 50 per cent noise reduction to the human ear,” senior engineering manager Steven Chan Si-yiu said. The new design, featuring a rubber coating made up of recycled tyres , was successfully tested along a 100-metre stretch near the Shau Kei Wan terminus in 2016. “Some residents nearby asked if services had been suspended because they could not hear the trams pass through anymore,” Chan said. Additional benefits over the traditional concrete-lined tracks include better durability and shortened repaving time. But the upgrades come at a hefty price – each metre can cost up to HK$18,000, 40 per cent more than the current method. Chief Executive Leung Chun-ying offered a much-needed financial boost in his policy address on Wednesday, promising subsidies to cover 2.4km of track. Managing director Emmanuel Vivant estimated this grant would help them save HK$20 million. He revealed that four 90-degree bends around the Kennedy Town loop would be the first section to be upgraded, with other busy junctions in the pipeline. In a separate development, the operator confirmed that more 10 air-conditioned trams would join the fleet next year after a pilot scheme last summer received overwhelmingly positive feedback. A “cooler tram” has been in operation since June , picking up around 300,000 passengers and receiving a 98 per cent satisfaction rate. The goal is to retrofit air-conditioning systems into 30 to 40 trams, subject to government approval as well as the capacity of the electricity grid. The fares would be “different” from normal trams, but the management would not reveal details at this stage.