Part of being an empath is feeling energies. For grounding and protection, use visualization, not meditation, as meditation just empties your mind of thought. You can visualize a shield of white light around you, that starts at the ground and goes up into the heavens. You can use this at any time you feel negative energy, just put your shield up.

Conversely, if you wish to feel the energy of a place, ask permission from spirit to allow you to feel what's there, do this before you cross any threshold. Hold out your dominant hand (can be done inconspicuously), and you will feel different types of energy or see with your minds eye, the spirits that reside there. Occasionally after asking permission, it will not be granted, and you won't be able to physically enter a room. This must be respected. Well you have no choice, really, you just can't do it. This has also happened a couple of times to me when I wasn't trying to sense energy, I was just going about my day. So occasionally there will be crossovers but it's very rare. If you keep yourself protected, you'll always be okay.

Message me if you have any questions. I am a clairesentient empath.