I use an Incuview Incubator. Holds a steady humidity for along time.One of my incubators is an NR360 and I'll bet every hatch it falls to even below 20 a few times.
I catch that within hours (or at least a day). It's not so critical like temps are, and is an average. Had it been lockdown, then I'd worry. I set alarms for myself those last three days.
I keep my humidity between 35% - 45% for the first 17 days, then increase to 55% to 65% for lockdown.
I use one Hygrometer/Thermometer to monitor the house conditions. I base my temperature, & humidity in my incubator according to this.
Then I have 2 Egg O' Meters(Thermometers for front, & back), & a Hygrometer/Thermometer attached to the inner lid to monitor overall conditions in the incubator.
Every part of my incubator is monitored closely.
The Egg O' Meters have alarms set for if the temperature gets too high, or too low. But I don't have an alarm for humidity which is fine.
I'm a very watchful chicken mama.
