Florida Building Code Practice Exam

What is the maximum moisture content allowed for interior fire-retardant-treated wood at a relative humidity of 92%?

1. 15%

2. 19%

3. 28%

4. 25%

The correct answer is: 28%

The maximum moisture content allowed for interior fire-retardant-treated wood at a high relative humidity of 92% is indeed 28%. This standard is in place to ensure that the fire-retardant chemicals within the wood remain effective and that the wood does not contribute to fire propagation, which could increase the danger in high-moisture environments. Fire-retardant-treated wood is specifically designed to resist ignition and slow down combustion; however, it is essential to maintain proper moisture levels to ensure the longevity and effectiveness of the treatment. At 92% relative humidity, the likelihood of wood absorbing moisture is heightened, thus allowing for a higher maximum moisture content threshold like 28%. Lower thresholds such as 15%, 19%, and 25% may not be suitable under those conditions as they don't account for the reality of high humidity environments where wood can naturally take on additional moisture. This option recognizes the practical aspects of real-world applications of fire-retardant-treated wood in humid climates.