The wings have four panels each about the size of a house door(ish). The inner three on each wing are lift dump spoilers and the outer ones are differential roll spoilers only. On a control check, you unlock the column, ( a small clip on bracket on the left column ) and while the PF pushes the rudder each way, the PNF will push to all four corners or more usually push to front, left and right then back into skipper's fat gut. This will produce different external effects depending on relative wind and strength as main flight controls are servo tab controlled, with limit direct control.
On the 146, you'd need to pull the lever right back for first airbrake and then spoiler, in that you will never see the dump spoilers out without airbrake fully out as well. On the RJ you may see spoilers deploy at high speed, but this usually indicates an unprofessional **** driving as going that fast is damn right stupid.
I query the logic of pulling all the spoilers to help keep taxi speeds down as well. If you are going that fast that they'd help, again hand your licence over please.
The 146/RJ suffers from light weight keeness to go, and the old school technique of shutting outers down on taxi in, works wonders. We got stopped from doing that when our management went from common sense to **** by numbers. Tyre and brake wear has now gone up loads.
The brakes drag, so taxi-ing SLOWLY is how you keep speeds down and brakes from getting too hot. Brake down to walking pace, then let it go for a minte and do the same again. That's how I was taught by an old Gentleman, now retired.
Hope the info helps.