Snubber to relay for Fan

[upper copper]

I need to add snubber in relay for the fan as the regulator makes voltage spikes and hinders the other channel in 4 channel relay!
So where should I keep snubber
Parallel to NO or connecting NO and COM?

[daring meteor]

snubber capacitors go to the 2 power cables that go to the fan. so most likely the relay output and neutral.