I don't know about California because its the only state I know of that everything causes cancer .
Its a beautiful state though.
In VA its not a big deal but time consuming . You attend a 2 hour class . They provide supplies up to 100 birds I believe. except the applicators for band which you can buy from about any poultry supply place. Eggs are sent for testing. This is ongoing bi yearly process.
You must keep up to date records and we test ourselves.
This may be different for commercial operation but is not that bad for breeder , hobby backyard flocks.
I just haven't found the time yet to drive the 3 hours to the class, 2 hour class and 3 hours back.
They only have these classes once a year in 3 locations statewide. It on my 'Plans" list.
But you know as was said " Life is what happens while you are busy making plans " - John Lennon