It is hoped a new code of practice for designing and installing office ceilings will reduce the risk of them collapsing on workers during earthquakes.
The Association of Walls and Ceilings has drafted the code and said better planning for installing electric cables, air conditioning units and pipes in ceilings is needed.
The association's chief officer, John Parkin, said that, during recent quakes in Christchurch Wellington and Seddon, unrestrained and poorly planned ceiling infrastructure smashed together and burst above workers.
"Most of the design for these installations are done in isolation. But what we've found after the Christchurch earthquakes, and more recently in Seddon, is that these different systems have not been restrained against earthquakes. And in a decent shake they knock each other around and cause damage."
Mr Parkin said at present, companies independently design the placements, but the new code would require a coordinated design so every element was placed to withstand tremors.