What is the maximum relative humidity of a drying oven for SFRM density samples?

The correct answer, which indicates that the maximum relative humidity of a drying oven for Spray-Applied Fire-Resistive Material (SFRM) density samples is 60%, is based on industry standards and practices. In order to obtain accurate and reliable density measurements, it is crucial that the drying process occurs under controlled environmental conditions.

Maintaining a relative humidity of no more than 60% is essential because higher humidity levels can impede the drying process and lead to inaccurate results. Excess moisture in the environment can cause samples to retain water, impacting the measured density and potentially affecting the performance characteristics of the fire-resistive material.

This specific maximum humidity requirement ensures that the samples are dried uniformly and completely, providing a true representation of the material's density and ensuring compliance with required fire resistance ratings. In practice, adhering to this humidity limit helps to achieve consistency and reliability in test results, which is critical for the integrity of fire protection systems.