On February 10, 2012, the Canadian Commission on Building and Fire Codes forwarded a letter to ULC with copies to UL and the Provincial and Territorial Policy Advisory Committee on Codes, requesting that ULC withdraw their application of Load Restriction Factors (background) for fire tests conducted prior to the adoption of Limit States Design principles.
In response to growing concerns from designers, building officials and the construction industry, the CCBFC Standing Committee on Structural Design formed a Task Group, which included members of the CCBFC Standing Committee on Fire Protection, to specifically study the ULC S101 testing protocol and to make a recommendation. The Task Group recommendation, which was approved by the Standing Committee on Structural Design, was that the fire rating tests based on Working Stress Design load calculations be grandfathered, or more specifically that the ULC load restriction factors not be applied to reduce the factored moment and shear resistances when designing composite steel beams, non-composite steel beams and open web steel joists.
Please click here to link to the two letters.