Which aspect is NOT critical when applying SFRM to a column?

When considering the application of Spray-Applied Fire-Resistive Material (SFRM) to a column, it is essential to recognize that factors such as substrate cleanliness, ambient temperature, and application techniques play crucial roles in ensuring the performance of the fireproofing material.

Substrate cleanliness is vital because any contaminants—like dust, grease, or paint—can inhibit the adhesion of the SFRM, compromising its effectiveness. Likewise, the ambient temperature is significant as it affects both the curing of the material and its application properties. If the temperature is too low or too high, it can lead to issues such as improper curing or application that doesn’t meet specifications. Furthermore, the application techniques employed significantly influence the uniformity, thickness, and overall performance of the applied fireproofing, which directly relates to fire resistance ratings.

In contrast, column height is not as critical in this context. While the height of the column may influence the accessibility and method of application, it does not materially affect the performance of the SFRM itself. Fire resistance ratings are determined more by the thickness of the applied material and its uniformity rather than the vertical dimension of the structural element being protected. Therefore, while column height may be a factor to consider