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T.PD.M.V.2.3
(Al/2001)
3.5.2 Horizontal Clearances from carriageways
3.5.2.1 Table 3.5.2.1 gives the recommended minimum clearances between the carriageway and
obstructions on the footways, verge or central reserve.
3.5.2.2 Although railings, and traffic signs and their posts should generally comply with the
requirements of Table 3.5.2.1, on existing footways of District and Local Distributor Roads,
Rural Roads and Feeder Roads this may not always be possible without causing
considerable inconvenience to pedestrians. In these situations, therefore, railings and
signposts may be erected closer to the edge of the carriageway, but no part of the railing,
sign or its post should be nearer than 200 mm. On Trunk and Primary Distributor Roads and
Rural Roads if the hard shoulders, marginal strips and verges are maintained there should be
little difficulty in achieving the clearance distances in accordance with Table 3.5.2.1 for
traffic signs situated on the nearside of a road. However for a traffic sign located on the
central reservation it may be impractical for various reasons to provide the full horizontal
clearance and in these situations some reduction may be acceptable but the resulting
horizontal clearance should never be less than 450 mm.
Table 3.5.2.1.
Horizontal Clearances from the Carriageway to obstructions
Design Speed
km/h
50 or Less
Above 50
less than 80
Height of
object
i) Less than 3m
ii) 3m and above
i) Less than 3m
ii) 3m and above
80 and above Any height
Minimum Clearance where carriageway cross fall is:
Away or towards Towards object Towards object
object but not but not steeper and steeper
steeper than 2.5% than 4% than 4%
(mm)
(mm) (mm)
500
500
600
1000
1000
600 600
600 800
600
1000
1000
600
1000
1000