The Hong Kong Institution of Engineers made the call after a series of incidents, including the latest incident on Tuesday at an optical shop in Sino Centre in Mong Kok, where a 58-year-old man was injured in the head.

The institution noted that about 20% of buildings aged over 30 years old in Hong Kong are in poor or dilapidated condition, with over 5,200 buildings posing safety risks.

By 2046, it is expected that over 20,000 buildings, almost half of those aged over 30 years old, will be at risk.

"Buildings will inevitably develop different problems as they grow older, like humans.

If we wait until problems arise before tackling them, the time and money required will increase correspondingly," said president Barry Lee Chi-hong.

Concrete spalling, which is a common problem in older buildings, is typically caused by prolonged exposure to moisture, aging of concrete, minor cracks in concrete due to hot weather and temperature difference, or damage to waterproofing coatings.

Unauthorized building works can also pose risks of falling concrete.

While concrete spalling will not immediately endanger the building structure, it is a sign of a problem that needs to be addressed immediately.

If owners notice any obvious damage, such as water stains or rust on the surface, falling of canopies, tiles, paint or wallpaper, or cracks or bulges on the wall, they should seek inspections by registered inspectors rather than carrying out repairs by themselves.

If structural problems or concrete spalling are involved, owners should contact professional structural engineers as soon as possible to assess any immediate danger to the structure of the building and conduct repairs accordingly.

The institution has also updated a guide on building safety and maintenance to give owners a better understanding of maintenance procedures.

In addition, they suggest that authorities strengthen public education to raise awareness about building inspection procedures.