Which aspect is fundamental for the design and installation of private fire service mains?

The characteristics of the water supply are fundamental for the design and installation of private fire service mains because they directly influence the effectiveness of the fire protection system. Understanding the water supply includes evaluating the pressure, flow rate, and quality of the water, which are critical to ensuring that the fire suppression system operates effectively during an emergency. A reliable water supply ensures that adequate water can be delivered to all parts of the system, enabling it to effectively combat fires when needed.

In contrast, while the cost of materials, compatibility with existing structures, and the brand of sprinkler systems may influence design and installation decisions, they do not hold as much foundational significance as water supply characteristics. The functionality of the fire service mains is primarily determined by whether the water can be delivered at sufficient quantities and pressure to meet the demands of the sprinkler system. Therefore, without adequate water supply information, the entire system may be compromised, leading to potential failure in firefighting efforts.