Red Seal Concrete Finisher Practice Exam

When should curing compounds be applied to fresh concrete?

1. Immediately after the surface is finished

2. 24 hours after the pour

3. Only when temperatures drop

4. Before the initial set begins

The correct answer is: Immediately after the surface is finished

Curing compounds are essential for maintaining moisture in fresh concrete, which is crucial for proper hydration and strength development. The ideal time to apply curing compounds is immediately after the surface finishing is complete. This timing ensures that the curing compound can effectively seal in moisture and prevent water loss during the critical early stages of curing, especially before the concrete has fully set. Applying the compounds immediately helps protect the surface from drying too quickly due to environmental factors such as wind, heat, or sun exposure, which can lead to cracking and weakened concrete. Additionally, curing compounds work best when the concrete is still in its plastic state, allowing for better adhesion and effectiveness. Using curing compounds too late — such as after several hours or the following day — diminishes their effectiveness, as the initial set may have already begun the hardening process, and moisture retention becomes harder to control. Therefore, the correct timing for applying curing compounds is critical for achieving optimal concrete performance.