Public safety sometimes relies on having crowds behave in sensible ways. I’m always surprised when using underground train systems that there are signs saying “keep to the right when ascending” and yet the stairs themselves offer no incentive to conform.
Frequently, the whole system clogs up because of someone with a wheeled suitcase deciding to climb on the side that is being used by 1000 others to descend.
Today’s invention is a side-by-side, two-lane staircase which makes it easier to climb on one side and descend on the other.
The stair risers are of different heights. This alone stops people using them in a daydream or when eg running.
The red profile is best suited for ascending, having bigger steps at the bottom and shallower ones at the top (when you are getting tired).
The blue profile has deeper steps nearer the top, but once one’s downward momentum has gathered, the steps get smaller towards the bottom (so that one’s knees and ankles don’t suffer from ever-increasing jolts on the way down).