Blade guards for power tools such as table saws are disclosed. The blade guard may include a guard that pivots up and down to allow a workpiece to move past the guard, a dust collection channel, and a pivot mechanism which maintains the dust collection channel in an operable condition as the guard pivots up or down. The guard may also function as a wood stop and it may include anti-kickback pawls. The blade guard may be part of a dust collection system and may be connected to a vacuum system by a conduit such as a flexible hose.