Usually low band for some, others may use a state trs if they have one.
Most the uhf FEMA stuff will be encrypted and many are operations or channels in uhf for federal have been coming out encrypted.
There is a few channels in those which dont allow it but most will be encrypted.
I know it varies by state so I can only comment for what they use where I am.
I'd search the low band, and look in the database here for any sar, FEMA stuff. If nothing is listed maybe a local will chime in.
As one knows operations tend to occur with low band or hf then the unit will be on another frequency to communicate with its group having a comms tech monitoring the unit and hf or low band. So ymmv depending where you are and how protocol is in state.
You may get lucky and they all use trs talkgroups in clear from mobiles and portables.