Rationale

Both ASTM E84 and UL723 contain guidance on how flame spread, and smoke developed index values are established based on the conduct of multiple tests. However, ASTM E84 does not consider scenarios where the flame spread and index values from sets of tests have broad ranges. In UL723 for these scenarios, either the higher values are reported as the index or the range as tested is represented. This avoids situations where high (or low) flame spread, or smoke developed values are attained in data sets but may not be represented accurately through the expression of an average. This proposal intends to include additional guidance on these scenarios where the values exceed broad ranges. Considering that both ASTM E84 and UL723 are used interchangeably throughout many building and fire codes, this proposal also intends to maintain basic harmony between ASTM E84 and UL723. Based on previous ballot activity (WK77776), this procedure was updated to address concerns that the 10-point threshold for flame spread for assigning either the highest value, or the range of values, was too strict for multiple test results where all flame spread values are over 50. A new procedure was balloted for Sub-committee and Main Committee concurrently in 2024 to address those concerns. The results of that 2024 concurrent ballot (E05 (24-02)) have been discussed in detail by the Task Group and this new ballot was developed to address negative voter suggestions with assistance and collaboration with Jason Smart. This includes a graphical representation for flame spread for the ease of determining how the procedure is to be applied based on minimum and maximum flame spread values. A chart is provided for reporting FSI as proposed in Figure X3. A similar chart for SDI has not been included in this proposal because the 50-point spread threshold specified for averaging of the SDI values is constant across the entire range of SDI values all the way from 0 to above 450. The chart shows a diagonal stripe of uniform width (unlike the chart for FSI) and therefore, would not be as useful.