Which of the following best describes a characteristic of low pressure gas lines?

Low pressure gas lines are predominantly found in residential settings, where they supply natural gas or propane to appliances like furnaces, water heaters, and stoves. These lines typically operate at pressures significantly lower than those designated for commercial or industrial applications, which is why they are suitable for domestic use.

The other characteristics presented in the options do not align with the definition of low pressure systems. Low pressure gas lines do not operate above 25 psi; in fact, they operate below that threshold. While safety checks are essential for any gas system, they are not exclusive to low pressure lines and therefore do not particularly define them. Additionally, constructing low pressure gas lines from high-strength steel is not a common practice; instead, materials like polyethylene and copper are more frequently used for this purpose. Thus, identifying their typical application in residential settings accurately captures the essence of low pressure gas lines.