How do you predict and control valve noise?

Valve noise prediction: calculate using IEC 60534-8 or ISA-S75.17, based on flow rate, pressure drop, valve type, and piping. Sources: aerodynamic (gas expansion, high velocity), hydrodynamic (cavitation, flashing), and mechanical (vibration). Noise limits typically 85 dBA at 1 meter (operator exposure). Control methods: source treatment (low-noise trim, multi-stage, expanded outlet), path treatment (acoustic insulation, heavy-wall pipe), and avoid critical conditions. Low-noise trims divide flow into multiple small passages, reducing turbulence. Specify noise prediction in valve datasheet and verify during commissioning.