Yes sir, if they are on new trucks they have to be DOT/FMCSA approved. Unfortunately many older trucks (and passenger vehicles) run lights that say "For off-road use only", which is pretty dangerous when everyone around is blinded. Our fleet used to be all
T-800's (about 65 tractors at our location) and we had some guys that would try to swap out the standard sealed beam headlights with some of those ultra bright "For off-road use only" headlights. That is obviously illegal, so it did not go over too well. At the time we had a perfect CSA score, and we don't need dings over those kind of shenanigans. Unfortunately our score has slipped a bit because of some folks that wanted to hire inexperienced drivers who think more about speed than safety. Luckily they seem to be realizing that now and reversing course.