I have seen people use laser pointers at meetings and speeches we used them when i was in the seminary . I have no problem with anyone having a 5mw laser regarding other people being around or rather in public. Construction sites use laser levels all the time so I see no real 4 alarm fire emergency using a PROVEN 5 mw or less laser. I also would think that on the construction site you are a responsible individual and know what OSHA and Worker's comp and all that states on your particular work site. Also you will notive a lot of measuring devices use a red laser at 5 mw. So get a 520nm or 532nm laser pointer and make sure it is poutting out only 5mw. I think you'll be safe. Leave the high powered lasers in the privacy of your home. My feelings on this