What failure type happens when a sealant does not bond properly due to improper surface preparation?

Adhesive failure occurs when there is a lack of proper bonding between the sealant and the substrate, which can be attributed to inadequate surface preparation. This failure type indicates that the adhesive material (in this case, the sealant) is unable to adhere effectively to the surface it is intended to seal. Proper surface preparation is crucial, as contaminants like dust, oil, or moisture can impede the bonding process, leading to a significant reduction in the effectiveness of the seal.

In essence, if the surface hasn't been cleaned or treated correctly before the application of the sealant, the adhesive properties are compromised, resulting in failure at the interface where the sealant meets the substrate. This understanding emphasizes the importance of meticulous surface preparation in achieving a reliable and durable seal in firestop applications.