Quy định giá trị khoảng cao đều là:

h = 0.25m; 0.5m; 1m; 2m; 5m; 10m

h 0.25m; 0.5m; 1m; 3m; 5m; 10m

h = 0.25m; 0.5m; 1m; 2m; 5m; 15m

h = 0.25m; 0.5m; 1m; 2.5m; 5m; 10m