🕑 7 mins read
Print Friendly, PDF & Email

Traffic control devices encompass a range of tools and mechanisms employed for the management, regulation, and direction of traffic. These implements are designed to uphold specific criteria, including attentiveness, clarity of communication, responsiveness, and consideration for fellow road users. Among these tools, the most prevalent are traffic signs, traffic signals, road markings, and traffic islands. These devices and systems play a crucial role for all individuals utilizing the road, as they play a pivotal role in maintaining the smooth flow of traffic. In this particular piece, we will delve into the significance of traffic signals as both a device and a system intended to assist road users.

Traffic Signs

What exactly are traffic signs? It’s a question that might have crossed everyone’s mind while navigating the roads, steering a vehicle, and pondering how they truly function.

For traffic signs to serve their purpose effectively, they must be legally sanctioned. Their placement is crucial, ensuring they are easily visible and recognizable to road users well in advance. In terms of their lateral positioning, on roads with curbs, the sign’s nearest edge should be no closer than 0.6 meters to the curb’s edge. Conversely, on roadways devoid of curbs, such as rural highways with shoulders, this nearest edge can be situated anywhere from 2.0 to 3.0 meters away from the carriageway’s edge.

These signs should be affixed to signposts adorned with alternating black and white bands of 25 centimetres each. Additionally, the reverse side of all sign plates should be painted gray. Specifics such as size, shape, colour coding, symbols employed, and sign placement should adhere to guidelines established for each respective category.

The classification of traffic signs is based on the Indian Motor Vehicles Act and can be divided into three distinct categories:

  1. Regulatory Signs
  2. Warning Signs
  3. Informatory Signs

Regulatory Signs

Regulatory signs also known as mandatory signs are designed to inform the road user of certain laws, regulations and prohibitions. Violation of these signs is a legal offence. They are usually circular in shape however some are specially designed. The regulatory signs are classified under the following sub-heads:

  1. Stop and Give-Way Signs
  2. No Parking and No Stopping Signs
  3. Prohibitory Signs
  4. Speed Limits and Vehicle Cantor’s Signs
  5. Compulsory Direction Control and Signs
  6. Restriction Ends Signs

Colour of Regulatory Signs

The colour of the Regulations or Mandatory signs shall be a white background with a red border and a black graphical symbol.

Location of Regulatory Signs

The regulatory signs are usually located on the left side of the carriageway to face the approaching traffic. There should be enough distance from the point where regulatory action is required to the location of the sign, to give the drivers adequate time to decide.

Image by jcomp on Freepik

Types of Mandatory Signs

  1. Stop sign

This sign is intended to be used on roads where traffic is required to stop before entering a major road, and where it is intended that the vehicle shall proceed, past the stop line only after ascertaining that this will not cause danger to traffic on the main road. The sign shall be in an octagonal shape and shall have a red background and white border. The word “STOP” is centrally written in white.

Types of RoadsSize (W X H) mmFont Size (mm)
Asian/National
Highways
900 X 900150
Thromde Roads750 X 750125
Dzongkhag & other
roads
600 X 600100
Table 1. Sizes and Dimensions of the “Stop” sign
  1. Give Way sign

This sign is used to assign the right of way to traffic on certain roadways at intersections, whereby the vehicles controlled by these signs are required to give way and need to slow down or stop when necessary to avoid interfering with conflicting traffic. This sign shall be an inverted equilateral triangle with the apex downwards. It shall have a red border and white background with a black graphical symbol.

Types of RoadsSize (H) mmFont Size (mm)
Asian/National
Highways
900120/95
Thromde Roads750100/80
Dzongkhag & other
roads
60080/65
Table 2. Sizes and Dimensions of the “Give Way” sign
  1. Direction Signs

These signs shall be circular in shape. It should be indicated with a blue background and white border with white graphical arrow symbols or white background on the plate as indicated in Figure 3. The size and dimensions of the signs shall be as prescribed in Table 3. They are used to indicate directions.

Types of RoadsSize (H) mmFont Size (mm)
Asian/National
Highways
550 X 900750
Thromde Roads450 X 750600
Dzongkhag & other
roads
350 X 600450
Table 3. Sizes and Dimensions of the Direction signs
  1. Prohibitive or Restrictive Signs

These signs usually give instructions to road users to prevent from making manoeuvres that are not allowed. They cover both junctions and the sections of roads between junctions. This sign shall be of circular shape with a red border, white background with the black graphical symbol and a red annular or red disc with a white symbol or on white plate background

Types of RoadsSize (H) mm
Asian/National
Highways
750
Thromde Roads600
Dzongkhag & other
roads
450
Table 4. Sizes & Dimensions of Prohibitive Signs
  1. Speed limit Signs

The sign is usually circular in shape with a red border, white background and black graphical symbol. These signs shall be erected at the beginning of any section of road or the side of the structure which is subject to prohibition so as to face entering traffic.

They are commonly used at the approaching of structures like bridges, culverts, narrow roads, infrastructure, etc.

Types of RoadsSize (H) mmFont Size (mm)
Asian/National
Highways
750250
Thromde Roads600200
Dzongkhag & other
roads
450150
Table 5. Sizes & Dimensions of parking and No Horn Signs
  1. No Horn Signs

This sign shall be of circular shape with a red border, white background, black graphical symbol and red annular as shown in Fig.7. These signs are used in areas where an audible warning device is prohibited. The NO Horn sign is usually erected in the vicinity of hospitals, schools, libraries, etc.

Warning Signs

Warning signs are known as cautionary signs that are used to warn road users of certain hazardous conditions that exist on or adjacent to the roadway. The warning signs are in the shape of an equilateral triangle with its apex pointing upwards.

Colour of Cautionary Signs

They have a white background with a red border and black symbols.

Location of Warning Signs

Warning Signs are generally installed on the right side of the carriageway so that they will convey their message most effectively. However, in exceptional circumstances, the sign may be erected on the left side of the carriageway. In Thromde areas, advance warning signs should be placed at not less than 20 m or more than 100 m in advance of the hazard, while in rural areas the signs should be placed at not less than 60 m nor more than 160 m in advance of the hazard. In any case, normal traffic speed and the action required by the driver will influence the distance between the posted warning sign and the hazard. The travel distance is, therefore, the distance the driver needs to understand and react to the sign message and to perform any necessary action. The distance between the sign and the hazard is called the advance posting distance.

Types of Cautionary Signs

The commonly used warning signs are, Right Hand/Left Hand curve, Right/Left Hair Pin Bend, Right/Left Reverse Bend, Steep Ascent/Descent, Narrow Bridge/Road ahead, Slippery Road, Cycle or Pedestrian crossing, school zone, Men a work, Gap in Median, Ferry, cross road, side road, T-intersection, Y-intersection, Major Road ahead, round about, dangerous Dip, Hump or Rough road, etc.

  1. Horizontal Alignment Signs

These signs are used in conjunction with pavement markings and delineation to advise motorists to change the roadway alignment. The uniform application of these signs conveys a consistent message that establishes driver expectancy and promotes effective roadway operations.

  1. Intersection and Junction Signs

These signs are used in intersections and junctions including traffic circles. Intersections are classified into 3 – ways, 2 ways, 5 ways etc. depending on the number of road segments. This sign instructs vehicles entering the intersection to give way to vehicles going straight ahead.

  1. Road Width Signs

These signs are used to give warnings related to road width restrictions as shown in Fig.12.

  1. Road Obstacle Signs

These signs are used to indicate the obstacles on roads like uneven roads, steepness of road or any other situations that cause obstruction on the road. Some examples of these signs are indicated in Fig. 13 and Fig.14.

Informatory Signs

Informatory signs are called guide signs. These signs are used to provide information and to guide road users along routes about the location of facilities in the vicinity of the road or about the destination. The information could include names of places such as recreational, tourist, and cultural interest area signs and emergency management signs, sites, directions to the destinations, distance to places, etc.

Colour of Informatory Signs

These traffic signs are generally rectangular in shape with a longer side horizontal. But it has different colour codes for different types. However, signs have a white or yellow background with a black border and black arrows and letters. Letters are inscribed in English and other necessary languages.

Location of Informatory Signs

Informatory Signs should be generally located on the left side of the road where a driver would expect to find them always. However, in urban situations with wide medians and roadside development, mounting signs within the median may be suitable. It can also be mounted above the carriageway in special conditions.

Types of Informatory Signs

The signs of this category includes:

  1. Direction and Place Identification Signs
  2. Facility Information Signs
  3. Other Useful Information Signs
  4. Parking Signs
  5. Flood Gauge

It may also include designation signs, Direction Signs, Re-assurance signs and Route Marking.

  1. Advance Direction, Intersection Direction and Reassurance Direction signs

These traffic signs shall be with a white legend on a standard green background. Green for highways and blue for Thromde and other Roads with black or white legend. The Dzongkha word shall be bigger in size than the English word and placed above the English word as shown in Fig.15.

  1. Intersection Direction Signs

These signs complement advance direction indicators and ought to be positioned at critical intersections or decision points, illustrating the destinations accessible via the intersecting roads. If the primary destination has already been indicated on the advanced direction sign, it should be reiterated on the intersection direction sign. While intersection direction signs should not display distance indications—since such information is commonly provided on reassurance direction signs after intersections—the present sign specifies the direction of the road and the destination’s name, utilizing an arrowhead to indicate the route.

  1. Reassurance signs

This sign is intended to be installed on significant roads after intersections or junctions, providing drivers with reassurance that they are headed in the correct direction. The name of the location should be displayed in both the local language and English. The local word should be positioned appropriately relative to the English words, adhering to regulations that dictate the local word should be larger in size than the English word.

  1. Service signs

This sign provides road users with information about the whereabouts and accessibility of various services, such as hotels, restrooms, hospitals, and more. It is characterized by a white symbol on a blue backdrop.

FAQs:

Q: What are the types of traffic signs?

Ans: There are three types of traffic signs as follows:
1. Regulatory Signs
2. Warning Signs
3. Informatory Signs

References:

  1. BTS 33:2017, Road Safety Signs and Symbols, Bhutan Standard Bureau, Thimphu, 2017
  2. The Motor Vehicles Act, 1988 | Ministry of Road Transport & Highways, Government of India. (n.d.). https://morth.nic.in/motor-vehicles-act-1988
  3. Khanna, S.K. & Justo C.E.G. (2001). Highway Engineering (8th ed.) Nem Chand & Bros., Civil Lines, Roorkee.
  4. Dixit, P. (2020). Gate Tutor 2020. Solved papers 2019-2012 & 5 Practice Sets. Arihant Publications (India) Limited

Loading

Tshering Dorji

Tshering Dorji is an experienced Assistant Engineer with a 10 years of work experience in building construction and design, particularly in the design of school buildings and residential structures.

Leave a Reply