These are the stairs. The supervisor was throwing those red containers cart from up there.
Our pcm is next to the stairs so the trash on the carts where falling in top of the drivers.
The driver decided to go up there to stop the unsafe situation when the SUP came back with another 2 carts, our pcm supervisor told the other SUP not to throw the carts, at this point the driver is walking down the stairs, yet the supervisor decided to let another cart go so the driver has to stop walking down and brace for impact, when the cart hit him, the SUP walked down the stairs and just said " sorry, can you go down please", then the driver went looking for his Steward, the our supervisor said it all could had been avoided if the driver never went up there in the first place.