Are W-column readings below 1-7/16" considered acceptable?

For this question, the focus is on the acceptability of W-column readings in the context of spray-applied fireproofing. A reading of less than 1-7/16" for W-columns indicates that the fireproofing thickness may not meet the minimum required protection levels established by codes and standards. However, a reading below this threshold may be deemed acceptable under certain circumstances.

The correct answer indicates that readings below 1-7/16” can be considered acceptable, likely due to possible allowances in specific applications or scenarios. For example, if the column is part of a structure where other safety measures or mitigations are in place, the requirement for thickness may not be as stringent. Additionally, there might be guidelines that permit lower thicknesses in temporary installations or in conditions where other fire resistance measures are employed.

In practice, this means that while standard thicknesses are critical for ensuring adequate fire protection, there are contexts or conditions where less material may still comply with safety requirements, especially if supported by engineering evaluations or if the situations are carefully managed.