He was standing outside the six-storey warehouse when he was shaken by an explosion.
Parts of wooden furniture and concrete slabs came crashing down nearby, one of them almost hitting him.
The security guard, who wanted to be known only as Mr Shankar, was on duty yesterday afternoon at the Four Star building at Kallang Place.
"There was a lot of smoke coming from the windows and the concrete slabs which fell were really big," he said.
"Thank God no one was hurt."
Each slab was as wide as his shoulders, said the 47-year-old.
When Mr Shankar realised that the fire was on the fifth storey, he sought help from three workers to help evacuate others in the building.
The workers went from the second to fifth storeys to inform people of the fire, while Mr Shankar called the Singapore Civil Defence Force (SCDF).
Mr Shankar said: "We still don't know how the fire started, but the wooden furniture probably fuelled the flames and made it bad."
The unit on fire sold wooden furniture, he said.
The fire started around 12.30pm.
Firefighters extinguished the flames within an hour using three water jets.
Two SCDF officers suffered from exhaustion as a result of fighting the blaze and were taken to hospital.
A tenant on the fifth storey, who wished to be known only as Madam Tan, said she was initially unaware of the fire.
The 56-year-old said: "They came knocking on our doors to tell us about the fire and we ran for our lives. I'm really glad that our neighbours were really helpful.
This article was first published on August 30, 2014.
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