TALL BUILDINGS in the US are designed using increasingly unsafe fire codes, a leading American fire protection expert warned last month.
'Fire resistance in today's tall building codes is only half that of the original Uniform Building Code in 1927, ' said Portland Cement Association regional code services manager, Jim Messersmith.
Since the World Trade Center attacks last year, proposed changes to US international building codes to increase fire protection have been rebuffed.
Messersmith said code changes in states other than New York were unlikely, as the perceived terrorist threat was lower.
Engineers in the US are allowed to reduce fire protection by increasing the amount of sprinkler capacity.
This is known as 'sprinkler trade off'. Over time sprinklers have become mandatory - but sprinkler trade off has remained.
'If sprinklers do not control a fire for any one of many possible reasons, then the building's structural fire protection needs to be the same as a building without sprinklers, ' Messersmith warned.
US international building codes currently being drafted will require any building over 23m to have just two hour rated fire protection for columns and floors.