Hey i was thinking about building a small laser obstacle course maybe 20 feet long and 10 feet wide. I've been doing some laser research but im not sure what equipment would be safe to use. I want the beam to be clearly visible but it seems most really visible lasers are a little dangerous. I was also going to use cheap mirror tiles you can buy in bulk but im not sure how dangerous a stray reflection could be or how much of the beam would be absorbed by the mirrors. Say i used a 5mw laser to stay safe, would it be visible and would it extend as far as i needed it to? also if i did use a more powerful laser, would that burn out the trip alarms that you can buy on the internet? thanks for your time