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T.P.D.M.V.2.3
(Al/2001)
Table 3.7.7.2
Design Standards for Footbridges and Subways
Minimum :#
effective
width
Minimum :#
vertical
clearance
Ramps :
Footbridges
2m (except on stairs to Tram or similar
platforms where a lesser width is necessary
because of limited space)
5.1m
Subways
3tn
2.3m (for length less than 23m)
2.5m (for length not less than 23m)
Where possible both ramps and stairs should be provided on all approaches.
Desirable maximum gradient = 1 in 12
Stairwavs :
Landings :*
Handrails
_•
Absolute maximum gradient = 1 in 10
Centre line of circular ramps should never exceed 10%
Stepped ramps should not be provided
Desirable maximum height of risers = 150mm ) Values chosen for
Absolute maximum height of risers = 165mm ) riser height 'R' and
(in exceptional circumstances only) ) tread width T
Desirable minimum width of tread = 280mm ) must satisfy both:
Absolute minimum width of tread
Desirable maximum flight of steps
Absolute maximum flight of steps
= 250mm ) 2R+T = 580 to 600 T x
R = 42000 to 45000
= 1 2 risers
= 1 6 risers
Ramps steeper than 10% to have landings at vertical intervals not greater than
3500mm.
Ramps of 10% or less to have landings at vertical intervals not greater than
3500mm where space permits.
Desirable length for stairs
Absolute minimum length for stairs
Desirable length for ramps
Absolute minimum length for ramps
Width of all landings
= 1500mm - 1800mm
= 1 000mm
= 2000mm
= 1 500mm
= Not less than that of the approach
stairs or ramps
Handrails must be provided on both sides of all ramps and stairways, and
consideration should be given to the provision of central handrails on stairways
4000mm wide or more.
* Ramps with gradients above 10% require approval from the respective AC for T/Region.
# Adequate allowance should be made for railings/handrails, lightings, finishes, etc in
calculating the clear width and height of footbridges/subways.