Traffic signals in India. What is the first thing that comes to your mind when you hear the civil engineering subject? The one who disturbs the rhythm of your journey without your permission, right? Jokes apart, it plays a relevant role in the traffic management of the country. Being wide and heterogeneous in nature, it is not a cakewalk to control the huge population including you and me.
Before we get into the details, let me tell you something important. Traffic signals in India and traffic signs are not the same!
- Traffic sign v/s signal
- The importance of traffic signals
- Mechanism of traffic signals in India
- Advantages of traffic signals in india
- Types of traffic signals
- Types of traffic signal system
- Warrants for traffic control signal in india
Traffic sign v/s signal
There is often a misconception that traffic signals and signs are the same. But the truth is that both are traffic control devices, but different. Traffic signs are placards provided to guide you in the journey. Signals are placed only at the main intersections to manage the traffic.
For example, imagine a junction where heavy traffic is found usually in the north-south direction. If there is no much traffic in the east-west direction, traffic signals are not required at the junction. Yeah, simple logic.
The importance of traffic signals
Growing traffic density is a significant issue. Insufficient expansion of available road space also contributes. These factors have resulted in congestion during peak hours. They have caused related delays on urban roads around the world. It results in increased travel time, which reduces the performance of the transport network. This problem is more serious on urban roads with frequent intersections. Intersections are the main points of conflict for traffic movements. Traffic signals at the main intersections can curb the situation.
Mechanism of traffic signals in India
The design of signals will be straightforward. It shows a green light where there is less traffic. It shows red where there is more traffic. It also considers the pedestrians who may cross the road. It allots a minimum of 10 to 15 seconds for their crossing. Another interesting fact it considers is that the overall waiting time should not exceed 120 seconds in normal situations. This is the average tolerance level of humans.
Advantages of traffic signals in india
- Provide orderly movement
- Minimizes the number of conflicting movements
- Increase capacity
- Interrupt heavy traffic to allow other traffic to enter or cross
- The coordinate continuous movement of traffic at the desired speed
- Promote driver confidence
Okay. Let’s see the varieties now.
Types of traffic signals
Traffic signals are broadly classified into three.
Traffic control signals
These are the signal lights in red, green and yellow. Red to stop, green to go and yellow to get ready. Obviously, you have seen the rangoli of colors in your life.
Traffic control signals are further divided into 3.
Fixed time signal
These signals operate at fixed time periods without considering the real time traffic.
Manually operates
This type of signals are manually operated which makes it more reliable.
Traffic actuated
This includes semi actuated and fully actuated signals. The timings are real time.
Pedestrian signals
These are the signals for pedestrians who cross the road or walk along the footpaths.
Special traffic signals
All other signals which don’t come in the previous categories belong to this type.
Types of traffic signal system
The whole system of traffic signals in India are divided as follows.
- Simultaneous system
- Alternate system
- Simple progressive system
- Flexible progressive system
We have seen different faces of signals. Now, let me get you the warrents for traffic control signals.
Warrants for traffic control signal in india
1. Minimum vehicular volume warrant
Case 1- The average traffic volume for 8 hours should be at least 650 vehicles/hr. This applies to both approaches on major streets with a single lane. It should be 800 vehicles/hr on streets with 2 or more lanes.
Case 2- Minor street (One direction atleast 200 veh/hr- single lane
250 veh/hr- two lanes
Case 3- >60kmph, 70 percent increase in major case
2. Interruption to continuous traffic flow on major street with 1000- 1200 veh/hr that there is undue delay or hazard to traffic on minor road with a traffic 100- 150 veh/hr in one direction only during any 8 hours on average day
3. Minimum pedestrian volume movement
4. Accident experience warrant
5. Combination of warrants
Lastly, in areas where there is huge traffic, ramps are preferred. But ramps are not suitable to heterogeneous traffic through some of the planned cities have implemented them. Its better to use flyovers and over bridges in these cases.
MUST READ: Basic of civil engineering; Simple and in-depth guide
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