Print each venue's code and post it where that team clocks in. Scanning opens the time clock for that venue — employees pick their action and enter their PIN.
http://punch.thirdwavebbq.com.au/punch.html?venue=3
http://punch.thirdwavebbq.com.au/punch.html?venue=2
http://punch.thirdwavebbq.com.au/punch.html?venue=1