1) Confines

“ The confines of bollards and posts are determined 在 agreement 与 illustration contrary 和 take into account 这 following interpretations
• the height is measured from the face of the path;
• the overall range, 这 lowest of the confines, or the periphery are measured in the vertical aeroplane.
这 height must be at least 50cm.However, its range 或者 periphery must be at least 28 厘米, If the bollard or post is 50 厘米 high.
Still, 这 range or minimum periphery of its base is equally commensurable to its height, If the bollard or post is advanced than 50 厘米.
For caseHow high should bollards light be
• the height of the post is1.10 m at the veritably least for a periphery 或者 range 的 6 厘米;
• a bollard with a range 或者 periphery 的 21 cm is at least 60 厘米 high透明

2) Contraste

Differ is useful for the visually bloodied, helping them more perceive road cabinetwork.
As a general rule, 这 物品 的 road cabinetwork should differ explosively with its immediate surroundings.
Exemplifications
• A light-coloured bollard contrasts with a dark ground
• A dark bollard contrasts with a light-coloured structure
Still, 这 body of the bollard or post should differ explosively 与 top over a height 的 100 mm in the most common cases, If there isn’;t enough discrepancy with the surroundings.