A selection of a few points of interest from the following standards and regulations:

[1] ČSN 73 4130

• The edge of each step and landing must be provided with an anti-slip treatment.
• The treads in the stair arms of the same staircase should be of the same height and width. Skewed and special treads must have a tread width of at least bmin = 130mm at the narrowest point. [1]

• There shall be a maximum of 18 step heights per stair arm.[1]
• Ratio between step height h and step width b: 2h + b = 630 mm (600mm-650mm)[1]

• The optimum step height is 150-180mm.[1]
• The smallest step width at the exit line is 210mm, the smallest scale width at the exit line is 250mm.[1]

• The exit line for mixed arms shall be placed in plan at a distance of 1/3 of the width of the arm, measured from the outer edge of the curve of its curved part.[1]

• Through shoulder width B [1]
  Shall be a multiple of 600mm, which is the width of the passing lane for one adult.
  The handrail structure may not encroach more than 100mm into the clear width of the B-arm.
  B min. for detached houses 900mm
  B min. for dwellings 1100mm
• Approach height H1, clearance height H2 [1]

• Railings [1] :
  At the start and end of the arm, the horizontal part of the handrail must extend at least 150mm beyond the edge of the start of the change in arm level on the outside of the arm.

• Landing [1] :
  The embedded landing between two stair arms shall have a length Lp in multiples of 630mm increased by the width of the adjacent exit step b.

• Location of the door on the landing relative to the arm [1] :