Do air purifiers help with pet odor or just dander?

HEPA filters capture dander and hair but do not remove odors. For pet smells, you need an activated carbon filter, which adsorbs volatile organic compounds and odor molecules. Many pet focused purifiers combine HEPA and carbon filtration in one unit. UV C light can also help neutralize bacteria that contribute to pet odors, but carbon filtration is the primary odor removal technology.