Chadchart was speaking at a press event held on Monday (June 19) called by the Bangkok Metropolitan Administration (BMA) in response to a 6.0 magnitude earthquake reported off the southern coast of Myanmar earlier that morning. The tremors were felt by residents in several districts of Bangkok.
District chiefs of Chatuchak, Bang Rak, Khlong Toei, Lat Phrao, Bang Khen, Lak Si, Huai Khwang, Bang Phlat, Bang Khun Thian, and Nong Khaem reported that vibrations were felt in their areas, but no high-rise buildings were affected, said the governor.
“The BMA and research teams from several institutes have prepared for such an event,” said Chadchart, adding that the city has installed a seismic intensity meter on the 36th floor of the City Hall 2 Building in Din Daeng district to check the impact of earthquakes in city areas.
More seismic intensity meters considered for buildings in Bangkok
Deputy Bangkok governor Wisanu Subsompon, who joined Chadchart at the press event on Monday, said the seismic intensity meter on the top floor of City Hall 2 showed a peak of 3.5 milli-g during the quake, higher than the average value recorded at the foundation level of 1-2 milli-g.
The reading from the meter on the 4th floor of Chulalongkorn University’s Faculty of Civil Engineering building was 1.5 milli-g, he added.
“Buildings constructed before the enactment of the 2007 Building Control Act are able to withstand seismic intensity up to 50 milli-g at the foundation level and 150 milli-g at the top,” he said. “Meanwhile, those built after the act came into effect must comply with the regulations which mandate a capability to withstand 100 milli-g of seismic intensity at the foundation and 500 milli-g at the top.”
Wisanu said that the city had dispatched officials to check on high-rises in Bangkok after the tremor was reported and found no damage. He then concluded that the quake on Monday was mild and could be felt by people, but was not strong enough to cause damage to buildings.
Wisanu added that the city is considering installing more seismic intensity meters at public buildings in Bangkok to get more accurate readings in different areas across the city during earthquakes.
Earthquake drill has the same priority and importance as drills for fire and chemical leakage
Deputy governor Tavida Kamolvej said the BMA places earthquakes at the same level as fire and chemical leakage in its disaster prevention and mitigation plan, and will continue to survey the structure of buildings in city areas periodically to ensure that they comply with related laws and safety regulations.
“Earthquakes cannot be predicted so we have to prepare by installing measuring devices and setting up a system to alert the public,” she said, adding that the BMA is currently using the Line Alert platforms of the Department of Disaster Prevention and Mitigation and the Meteorological Department, which can also warn of PM2.5 air pollution levels.
Tavida added that other measures to ensure public safety from earthquakes is to educate the public about do’s and don'ts during earthquakes, as well as to run a drill periodically for both the indoors and outdoors.
“Although Bangkok is in the zone with minimal risk of impact for earthquakes, this knowledge can be useful when Bangkokians travel to other areas that have higher risk,” she added.
Toward the end of the press conference, Chadchart assured attendees that high rises in the city have been designed and built to meet safety standards by experienced engineers, and that their foundations must also meet the legal standard to withstand any disasters.
“Generally, modern buildings as well as residential houses can withstand a certain level of earthquake, as long as they meet legal standards regarding strength and flexibility of structure,” said the governor. “High-rises are subject to even stricter standards to ensure the safety of a large number of users and that the building’s functionality is still usable after the disaster. Public facilities such as hospitals and fire stations also conform to this practice.”