David Chipperfield AmorePacific – How did they manage the MEP in this concrete ceiling ?

Hi,

I was travelling in Korea and bumped into this really cool piece of work from David Chipperfiel architects, and even if the exterior isn't my fav (maybe a bit too monolithique, the size is MASSIVE !), I was in awe with the beautiful lobby space with the exposed concrete !

But it is a mystery for me to understand how do they manage to put all the MEP equipments in those exposed concrete ceiling.

https://preview.redd.it/652ewp63rf4f1.png?width=1349&format=png&auto=webp&s=062409746ac1214ad35f97de6a5067624d101842

https://preview.redd.it/psi03vmerf4f1.png?width=721&format=png&auto=webp&s=d08b3689408e370cb93ecf702ac4ec96a25c4eae

The small opening are just enough to install the various equipments heads, but how did they put inside all the pipes etc ? And left also the question on how do they do the maintance of these equipments with a solid exposed concrete ceiling like this ?