The recommended method of determining the exact friction loss of any appliance is to:

The best way to determine the exact friction loss of any appliance is to run tests with each appliance used by the department. This method provides the most accurate and specific data, as it takes into account the unique characteristics of each appliance, such as its design, materials, and any variations in manufacturing. By conducting actual flow tests, operators can measure the pressure loss accurately and gain a better understanding of how each piece of equipment operates under real conditions.

While manufacturer guidelines can offer useful starting points and standard friction loss calculators can provide general estimates, these tools may not account for all variables affecting friction loss in specific scenarios. Estimating based on previous data also introduces uncertainty, as it relies on prior experiences that may not align with current conditions or changes in the equipment. Running tests aligns with best practices in fire apparatus operation, ensuring that personnel are equipped with precise information for effective firefighting and incident management.