Mr Zhang Guohui was waiting in line at the Ministry of Manpower (MOM) Services Centre at about 3.30pm on Monday when the loud, shrill alarm went off.
"I was startled and I didn't know what was happening at first," said Mr Zhang, 34, a Chinese national who works as a construction worker here.
Before he knew it, MOM officials decked in bright orange vests acting as fire wardens began directing him and other members of the public out of the building.
"This way please," one fire warden said politely, pointing to the carpark in front of the building. "No need to rush," said another.
Mr Zhang soon found out from them that it was MOM's first fire drill at their new frontline division building at Bendemeer Road, which became fully operational in June this year.
"The fire wardens explained to me what was going on, and they were very patient and calm. No one panicked," said Mr Zhang in Mandarin. "I came down to make some inquiries about my work permit, but I understand this exercise is for everyone's safety."
About 800 people were involved in the drill, which was organised by the National Fire and Civil Emergency Preparedness Council (NFEC).
This is also part of its month-long Mass Fire Evacuation Drill campaign, which 172 premises have signed up for, said the Singapore Civil Defence Force (SCDF).
Within three minutes, all 400 members of the public were ushered to the carpark in front of the building, while staff were guided to the carpark behind. The SCDF also sent one fire engine and two fire bikes as part of the exercise on Monday.
As soon as everyone was evacuated from the building, the SCDF crew proceeded with a 20-minute lesson on the use of fire extinguishers.
Members of the public and staff were also invited to try their hands at putting out makeshift fires. Ms Pauline Chong, a fire warden and MOM's head of corporate development and services, said: "It was a very successful exercise.
"The fire wardens knew what to do, having been briefed prior to the drill, and everyone else cooperated. "We hope this exercise will allow everyone to know how to react in the event of a real fire.
"Customers were also given a queue number prior to the drill, so that they would not have to queue up all over again."
The counter staff were able to give instructions to the foreign workers in their native languages so the drill went smoothly, she said.
Operations resumed by 4.10pm.
Said NFEC chairman Alan Loh: "(The) drill has brought all of us together and given us the opportunity to think about emergency preparedness and fire safety.
"We must avoid encountering the painful consequences of not being aware, not being prepared and not being ready."
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