Things which help mitigate noise from a Nomad:
- keep it lubricated: https://docs.carbide3d.com/nomad-faq/what-oil-should-i-use-to-lubricate-the-linear-bearings/ — for the Z-axis on a Nomad 3 see: Care and Cleaning for Nomad 3 and Rail and linear guide maintenance
- placing the machine on a foam pad to prevent the tabletop from resonating
- put isolation pads under the table legs such as are used for an appliance such as a washing machine
Add an enclosure around the machine.