Full face respirators are better; again, make sure the face shield is ballistics tested. You can mount old pairs of glasses to the face shields of full face respirators.

If tear gas is seeping into your home or you know tear gas is likely to be deployed in your neighborhood, you can do the following: Set up wet towels in the doorjambs and windows. Turn off your HVAC systems, and build and use CR boxes. This isn't perfect, but it will help. CR box guide below: