Zero Harm

I never quite get these sorts of slogans. They sit alongside mission statements as strange noughties advertising speak I don't think we're supposed to think too much about them. If you do then it just raises more questions than it answers.

Is it a get out clause in case you get (seriously) injured while working on this site in the next five months? How much harm is there at the moment? There doesn't appear to be any sign of blood or stray limbs.