The treads should not be slippery. A rubber strip or grooves at the front edge of the tread help lessen the slickness
The handrail helps to keep balance.
An open staircase must have safety slats.
Make sure that the staircase is properly illuminated. Also two-way light switches are good to use.
Make sure there are no unnecessary things on the staircase that would make it easy to stumble on.
If there are small children in the house, we advise you to install the child safety gate that will help avoid the child wandering on the staircase unsupervised.