IEC 60335-2-89 requires a system with more than 150g of flammable refrigerant to be designed in a way that does not generate excessive vibration or resonance in the piping to the compressor.
The standard sets a vibration limit of 0.3g RMS (measured with a low pass filter of 200 Hz) at 90% to 110% of the rated compressor frequency, or across the complete speed range of a variable speed compressor.