CSLB Class B General Contractor's License Practice Exam

Which of the following lines does not require freezing protection?

1. Water

2. Gas

3. Drain

4. None of the above

The correct answer is: Drain

The line that does not require freezing protection is the drain line. Drain lines typically handle wastewater and are often designed to carry water away from structures. They are usually installed with a slope to ensure that any water within these lines flows out due to gravity, which minimizes the likelihood of standing water that could freeze. In contrast, water lines transport potable water and need protection from freezing to prevent the pipes from bursting, as water expands when it freezes. Gas lines also require protection, as any potential for gas leak risks can be heightened by structural damage from frost heave or frozen piping. Therefore, the correct answer is that drain lines do not require freezing protection, making them distinct from water and gas lines.