According to National Fire Protection Standard 13D, what is the rule of thumb for sizing sprinkler lines?

The guideline specified in the National Fire Protection Standard 13D emphasizes the importance of ensuring adequate water flow and pressure for effective sprinkler operation. The recommended sizing indicates that a 3/4-inch line is sufficient to supply one sprinkler, which allows for proper water distribution and minimizes the possibility of pressure loss that could compromise the sprinkler's effectiveness. Additionally, a 1-inch line can effectively supply two sprinkler heads, which reflects a balance between maintaining sufficient flow and accommodating multiple heads while adhering to hydraulic demand principles. Understanding these sizing rules ensures that the sprinkler system is both efficient and compliant with safety standards, allowing for effective fire suppression.