restriction
Quantitative or numerical limitations on accessibility of use of a place or object.
Restrictions include any quantitative or numerical parameters which describe who or what may enter or use a certain object or place, or how it may be used.
A restriction sets a permitted numerical boundary on access or use. It describes what is allowed rather than the traffic or occupancy actually observed.
Minimum speed and maximum speed are lower and upper limits on movement through a place. The applicable quantity and unit determine what each limit constrains.