A three-storey building collapsed on Thursday in the Little Falls area of Roodepoort, killing one worker and injuring 14 others.
Another worker was missing, believed trapped under the rubble, and the rescue operation was continuing on Thursday afternoon.
Half of the nearly completed office block was destroyed when the top two storeys collapsed on to the bottom storey.
Emergency workers had cleared rubble by hand around an area where rescue dogs from the police dog unit were trying to locate the missing construction worker.
Some of the sniffer dogs were being distracted by the scent of the construction workers’ bags.
Rescue efforts were further being hampered by rubble continuously shifting and settling into the hole where the missing man was presumed to be located.
Heavy equipment was removing rubble in areas where the dogs had not reacted, to decrease the chance of the equipment accidentally injuring the missing worker.
The mass of rubble, as wide and broad as four tennis courts, was very unstable with rescue workers stepping gingerly and keeping to stable areas only.
Private volunteers from K9 Offroad Rescue were being called in by Johannesburg disaster management officials to assist with and possibly hasten the rescue.
The Labour Department’s building inspectors were waiting for the engineering plans to ascertain whether there may have been a fault with the design of the building. — Sapa