The first serious laser I ever owned was a 20 watt ( on label only) Coherent argon, 3 phase, water cooled monster. I ripped off all of the fiberoptic stuff on it and my best guess is that I had somewhere above 10 watts of output. I dont have three phase here, so I took it to a friends shop at the corner of W. Esplanade and transcontinental I think. This was pre 9/11 and I fired it over the levee toward the lake. The police received reports and showed up, they weren't worried about air clearance, but they thought there might have been a weapon attatched to it. Funny looking back, but I was lucky at the time not to get in to trouble. I take safety much more seriously now. I was somewhat unprepared at the time because I really didn't expect to get it fire up. I remember Harahs Casino used an argon of about the same power just a couple weeks later for their grand opening.