Which environmental conditions could delay the curing of spray-applied fireproofing?

High humidity and low temperatures can significantly affect the curing process of spray-applied fireproofing. When the humidity levels are elevated, the moisture in the air can interfere with the evaporation of water from the fireproofing material, leading to prolonged curing times. Additionally, low temperatures can slow down the chemical reactions necessary for the material to cure properly. The combination of these two conditions may prevent the fireproofing from achieving its intended performance levels in a timely manner, which is critical for ensuring that fire-resistance ratings are met.

In contrast, while strong winds and heavy rainfall can present challenges during application and can affect the application process, they may not directly influence the curing process in the same way humidity and temperature do. Bright sunlight and elevated temperatures can sometimes lead to rapid curing but can also cause issues like cracking if not managed properly. Airborne pollutants and particulate matter may affect the surface of the applied fireproofing but do not typically impact the curing process as significantly as humidity and temperature.