2-button No Hold Safety, and several CCTV cameras focused on it
You put the 2-button No Hold safety on the press to cycle it. Plus light curtains or a physical drop-barrier if they are practical on that style machine. That's a no-brainer.
But to stop other horseplay or stupidity cold in it's tracks - and to show the insurance co. and OSHA how it happened... You have three or four security cameras focused on that press from various angles, and all connected to a DVR recording at high detail - 1280 X 1024 or eq.
And if you have more than one press like that in the shop, you need more cameras and DVR channels to cover them.
The Office has several high-res monitors on the wall where someone can be watching them. And if anyone even thinks about screwing around like smashing somebody's lunchbox into a pancake in that press, or bypassing a safety in normal use, they'll see it. And you make sure the employees know they are SO Fired, One Strike.
Even the "Owners Family Exemption" still gets you busted all the way back to the Mailroom for a year minimum, including the pay cut - the requirement is to count fingers and get to ten at the end of the day. Every day.