I am aware, I have taken a course that included firing in an enclosed room with ear protection and have felt the concussion. Not disputing that its significant but the fight or flight response has to come into play in this situation and deaden the senses to a point. I would never use a 223/556 rifle as my primary emergency source of protection in my house. Barrel length, recoil and bullet penetration are not what I would consider residential friendly. Adding a suppressor only makes the gun longer and more difficult to maneuver. Personal choice is a 9mm. I also have a 9mm PCC in the bedroom closet with a compatible magazine to the pistol. That gives me a total of 51 rounds from either firearm of 147g subsonic which is approximately 162db. We also have an alarm system with motion sensors and entry points that is set every night and battery backed up. Hopefully I will know if there is someone in the house. Our plan is to shelter in the bedroom on the opposite side of the bed from the door and call the police if the alarm system hasn't already. There is nothing in our house that is worth trying to hunt someone down. I would not go looking for trouble, rather let it come to me if they are so inclined. My intention is to never have to pull the trigger.