In addition to pipe diameter, length, and fluid properties, the fittings and valves used in a pipeline also affect the pressure loss. Fittings and valves cause additional turbulence in the fluid flow, leading to increased friction and pressure loss. According to a report published by the National Institute of Standards and Technology (NIST), the pressure loss in a pipeline due to fittings and valves can range from 10% to over 50% of the total pressure drop, depending on the type and number of fittings and valves used.