How to Avoid Falling Object Risks in Dense Urban Settings?

Ina dense urban setting like that of Hong Kong, the risk of falling objects from façades of tall buildings is ever-present, although thankfully infrequent and occasionally causes injury or fatalities. The latest such incident took place on the 4th of January when a piece of glass panel fell from the curtain wall of the well-known landmark building of the city - Manulife Financial Centre(Window glass falls from the top of Manulife Financial Centre in Kwun Tong and hits windscreen of moving truck - Dimsum Daily). Although it fell on the windshield of a moving vehicle underneath, miraculously no one was injured. The28 storey twin building blocks at Wai Yip Street in Keun Tong, Kowloon were originally known as the Kwun Tong 223. The construction was completed in 2008,and the building was renamed Manulife Financial Centre in 2009 as the global insurance giant Manulife Financial is the largest leaser in the building with  eight floors. The other prominent companies that occupy the building include PriceWaterhouseCoopers (PwC), The Jardine Engineering Corporation Limited andthe world's third-largest freight company CMA CGM.

The property was jointly developed by Henderson Land Development and Sun Hung Kai Properties and constructed by E Man Construction Co. Ltd. - a subsidiary of Henderson Land. "The two 28-storey Grade-A intelligent office towers are connected with a multi-storey structured thoroughfare on the top floors. The characteristic building form adopts a full curtain wall facade design. The superstructure works have been completed in 18 months; which is exceptional in the construction profession."

Incidents such as the above are an ever-present threat to all modern global cities with an increasing number of tall buildings. In December 2021, a 35-year-oldconstruction worker was killed when a piece of concrete fell on him while working on a renovation project of the State Theatre Building - a grade 1heritage building. In January of 2019, a 24-year-old woman was killed in an incident of a falling window in the Sham Shui Po area of Hong Kong. In September 2018, another incident of a falling piece of concrete from a30-year-old building killed a 56-year-old woman. Many other less significant incidents are reported at frequent intervals. Given Hong Kong's tall buildingstock of over 42000 buildings, out of which almost 21000 are over 30 years old, this risk is only going to get worse with time. Given such fatal outcomes, thesafety risks from falling objects can not be under-estimated or ignored. With such a prestigious and relatively newly built property such as the Manulife Financial Centre being involved in the current case, the above-mentioned incident should cause much concern to all stakeholders, including owners, leaders, regulatory authorities alike.


The Building Department of the Hong Kong Government promulgated two building inspection schemes in 2012 to address the above concern. The Mandatory Building Inspection Scheme (MBIS) requires safety inspection of all buildings older than30 years at least once every ten years. Similarly, the Mandatory Windows Inspection Scheme (MWIS) requires checking all windows and their components once every five years for all buildings older than ten years. While these schemes have helped improve the safety standards of the city's buildings, there are several lacunae that need to be addressed. For example, a large number of notices under the two schemes are not enforced for a long time (up to six years sometimes) for a variety of reasons. Traditionally, building inspectors carryout surveys to detect safety risks. The conventional approach requires the inspector to climb on scaffolding or gondola or use cameras with a telephotolens to reach as close to the sites of potential defects to study the image and document the same in their report. This procedure is often unsafe, time-consuming and expensive. It also yields variable results depending on the individual inspector's training, background and expertise.


In contrast, RaSpect Intelligence Inspection Limited - a four-year-old Hong Kong start-up incubated by Hong Kong Science and Technology Park (HKSTP) has introduced an alternative approach to building inspection. Founder Harris Sun, a computer science graduate, founded RaSpect to bring this approach to the inspection of tall buildings. RaSpect not only carries out an automated inspection of building facades using drones but also uses Machine Learning (ML) and Artificial Intelligence (AI) for efficient data processing. The cloud served where the data is automatically uploaded and processed also generates the inspection report endorsed by registered professional engineers. This process is not only safe but also reduces the time and cost of a typical survey of abuilding significantly. In the last four years, RaSpect has successfully inspected many iconic buildings of Hong Kong, including the International Commerce Centre (ICC) - the tallest landmark on Hong Kong's skyline. Its technology is making it easier, faster and cheaper for professional survey or sand inspectors to carry out building inspections and help make Hong Kong a safer city.