Like wearing a seat belt, most safety regulations feel completely pointless until they're not. Unfortunately, many construction workers, especially in countries with lenient worker safety laws, don't seem to care much about violating safety protocols. The result is work sites that make you wince, with disasters it doesn't take a genius to see coming. 

For example, one person here can be seen welding while standing on top of a fuel barrel. Welding while standing on anything unsupported is bad enough, but a barrel filled with flammable material while sparks are flying around is a recipe for disaster. 

As evidenced by the story above, there is a time and place for welding. That place is not the produce section of a supermarket, as much as one handyman featured here might think it is. I don't think anybody wants their "fresh" spinach to come with a little bit of molten metal on top of it. See those, and many more OSHA violations in this gallery of safety fails that will make you wince.