IRC : 79 -2019 Summary

SI NO Descriptions
1 Classification of Road Delinators
Roadway indicators
Median Markers
Hazard Markers
Object Markers
2 Roadway indicators / Delineators /Guide poles :
2.1 Design :
These are made by Mild steel with pure polyester powder coating with the minimum thickness of
powder coating of not less than 40 microns for protection against corrosion.
The post shall have an ellipsoidal or circular.
Height of the pole shall be 800 to 900 mm above the ground with about 200 to 300 mm base
which can be anchored onto the ground.
Mild steel guide poles shall conform to Type X1 sheeting specifications as per IRC :67 and ASTMD
4956.
Guide poles shall have substantial area allocated to exhbit alternate band of black paint and
white retro reflective sheeting which can provide added aesthetics as well.
The normal spacing between two successive guide poles shall be about 50 to 70 m center to
center In case of high speed interurben roads catering to high volume traffic
In case of low volume roads as well as rural roads located on rolling and hilly terrain , concrete
delineators can be used as these would be less costly.
2.2 Alternative guide poles in work zones :
Plastic drums with alternative red and white retro -reflective stripes of 100 to 150 mm wide
conforming to Type IV Standards (Reboundable work zone sheeting as per ASTM D 4956 Clause
S2) shall be used for rosdway delineation especially when it is temporary purpose in the event of
diversion ,road works etc.

The temporary guide posts shall possess a height of about 800 to 900 mm above the ground with
about 200 to 300 mm base enchored onto the ground .
Such temporary delineators shall have three stripes of retro reflective sheeting (each strip with
150 Sq cm or above ) of Type XI conforming to IRC :67 and ASTM D -4956.
2.3 Criteria for Use :
Normally , use of roadway indicators should be considered under the fallowing situations :
1 Curved Sections.
a Horizontal curves of radius 300 m or less.
b Verticle curves with inadequate visibility.
2 Straight Sections :
a Road sections where visibility is often poor due to mist, fog for snowy conditions.
b Reaches where the alignment appears uncerrain to the driever ,e.g pavement with transition,
temporary road diversion,etc.
c Road sections subject to frequent submergence and ponding due to storm water.
d Approaches to narrow bridges and culverts.
e valley side of hill roads.
f road embankment exceeding 3 m in height.
g Approaches to important intersections.
h Special problem points such as causeways and tunnels.
2.4 Placement and spacing :
As general rule , roadway indictors should be erected at the edge of the usable shoulder and in
case of kerbed sections at a distance of 0.6 m from the kerb face.
On straight sections, roadway indicators should be spaced uniformly 50 - 70 m from each other .
Recommended spacing for roadway indicators on horizontal curves.
Radius of curve (meters) Spacing on curve ,( s ) ( meters )
30 6
50 8
100 12
200 20
300 25
3 Median markers :
a Colour :
The marker body shall be producted in neutral black colour. The colour of the retro reflective
element shall be Florescent yellow.
b Material :
The plastic body of the FMM (Flexible Median Marker)shall be moulded from flexible
Thermoplastic Body.
c Dimension :
Height : The marker shall be a minimum of 180 mm.
Width : The marker width shall be a minimum 120 mm.
Body thickness : Minimum of 6.5 mm .
Shank Length : Each of the shanks shall not be less than 20 mm and depth shall not be less than 30
mm.
Reflective Area : Shall not be less than 90 cm square .
d Performance
Reboundability : The body of FMM (Flexible Median Marker)shall bounce back to its original
position after 750 numbers of hits using pendulum of 1.8 kg conforming to ASTM D 256 .
Tensile Test : Adhesion between the body and outer casing body of FMM (Flexible Median
Marker)shall withstand 50 kg tensile loads conforming to ASTM D 638 method.
4 Hazard markers :
These consisting of alternative black and yellow strips , sloping downwards at an angle of 45 0 towards side
of obstruction on which the traffic is to pass.
Hazards marker made with Type XI sheeting conforming IRC :67.
5 Object markers :
 The aluminium -backed flexible prismatic sheeting shall be made of yellow colored flexible
prismatic sheeting with non metalic prismatic lens formed in a transparent , synthetic resin as
retro reflective elements .

These sheets having yellow and black strips with aluminum backed flexible prismatic type VI
sheeting conforming to ASTM :D4956 specifications and standards of coefficient of retro
reflectivity. Flexibility and impact resistance applicable for reboundable devices.
These Object markes may be bigger if the conditions so warrant on the ground.
Appilication :
On the beam and post of the metal crash barrier (MCB)Wire rope barrier post.
Traffic police /Toll booth structures, entry and exit points of the tunnel structures.
Periphery of the roundabout as well as bull noses of the traffic island.
Installation :
Width of object marker shall be 300 mm ,and length of object markers may vary depending upon
the situations .but shall be minimum around 400 to 500 mm these reflectors are fully visible .

6 Installation :
A proper foundation with M-25 G grade of concrete shall be used for instalattion of all type of
delinetors.
Instalation may vary based an nature and stiffness of the ground ,and local conditions.
The delineators should positioned to retro reflectorised face, is perpendicular to direction if travel.
Orientation doesn’t change when instalation of posts .Perticularly when it is in cercular shape.
7 Maintenance :
Remove the dirt on delineators in periodically, especially after rains.
The ground around the delineators should be kept clean by cutting grass and bushes periodically.

Abbreviations:
ROW: Right of way
FMM: Flexible median marker
OHM: Object hazard markers
MCB: Metal crash barrier.
nimum thickness of
orrosion.

0 to 300 mm base

IRC :67 and ASTMD

of black paint and

to 150 mm wide
STM D 4956 Clause
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