Milan Gorai was riding his two-wheeler in Tollygunge after dark. A killer bump caught him unawares and his bike toppled leaving him and the pillion rider – his aged mother, sprawled on the road. While Gorai was slightly hurt, his mother succumbed to her injuries the next day at M R Bangur Hospital. It was one of the many accidents that don’t make it to the headlines and therefore go unnoticed.
Speed breakers not built to specifications kill. Yet our city fathers ignore the fact that speed bumps are often equally responsible for road fatalities as rash driving. Several city roads and highways have speed breakers that pose a threat to motorists and bikers. Instead of curtailing car speed, these unscientific and illegal speed breakers are essentially car breakers and real killers. 
Moreover, randomly built speed breakers don’t even benefit the pedestrians contrary to the general notion. Unlawfully built bumps in fact might lead to congestion and dilemma giving pedestrians less time to cross the road than they get in a properly planned traffic regulation system.
Generally, the unlawful speed breakers are knee jerk reactions from local populace supported by the civic body due to demands to construct a bump after accidents, ignoring the basics of road engineering.
As per a senior police officer, speed breakers often come up in various parts of the city at the behest of local residents.

This monster bump on Prince Anwar Shah Road continues to scrape the under-carriage of vehicles

SPECIFICATIONS
According to the Indian Roads Congress (IRC), a statutory body of road transport engineers, the specific norms for erecting speed breakers are guided by IRC under “Tentative Guidelines on the Provision of Speed Breakers for control of Vehicular Speeds on Minor Roads, 1996”.
In fact, according to best practices recommended by the IRC, speed breakers are not necessary on city roads because almost every road junction has traffic signals and, after late night, blink cautionary yellow lights, unlike the highways.

Speed breakers may be necessary only near schools or hospitals, the IRC said. On highways and semi-rural roads, rumble strips are preferred to humps.
However, ignoring such guidelines, the mushrooming, unauthorised speed breakers are often left unpainted and without advance warning signs in poorly lit areas, forcing drivers to brake suddenly causing more accidents than preventing them.

Speed breakers on the down ramp of Ma Flyover are responsible for the sudden braking and ramming vehicles from behind

An ideally designed hump should satisfy the following requirements:
• There should be no damage to vehicles or excessive discomfort to the drivers and passengers when passing at the preferred crossing speed.
• The hump should not give rise to excessive noise or cause harmful vibrations to the adjoining buildings or affect the other residents of the area.
• Above the design speed, a driver should suffer increasing level of discomfort (but without losing directional control and without any vehicle damage) depending on the extent at which design speed is exceeded.

Specifications for location of speed breaker:
• T-intersections of minor roads with rural trunk highways, characterised by relatively low traffic volumes on the minor roads but very high average operating speed and poor sight distances.
• Intersections of minor roads with major roads, and mid-block sections in urban areas where it is desirable to bring down the speeds.
• Selected local streets in residential areas, school, college or university campuses, hospitals, etc.
• In areas where traffic is observed to travel faster than the regulated or safe speed in the area.
• Any situation where there is a consistent record of accidents primarily attributed to the speed of vehicles. For instance when hazardous sections follow a long tangent approach or to temporary diversions, weak or narrow bridges and culverts requiring speed restriction for safety, on the minor arms of uncontrolled junctions and at railway level crossings, and sharp curves with poor sight distances and places of ribbon development, where the road passes through built-up areas and vehicles travelling at high speeds are a source of imminent danger to pedestrians.

GUIDELINES OF INDIAN ROADS CONGRESS FOR SPEED REDUCING MECHANISM
IRC suggests a number of engineering measures to control vehicular speed as follows:
• Posting of mandatory speed limit signs, use of flashing beacons to alert drivers, road markings of various types, etc.
• There may be cases, particularly on secondary/tertiary roads and on residential streets in urban areas, where certain physical constraints may become necessary for effecting control on vehicular speeds. In this regard, three types of devices, namely, speed breakers, rumble strips and width restrictions have been used successfully. Choice among these will depend on local factors such as the type of area traversed, the type and volume of traffic, the extent of speed reduction desired, and other local factors. However, speed breakers, in particular, are meant mainly for residential areas, minor roads, and similar situations. Their use on major inter-city roads outside urban areas is not considered good engineering practice and the Indian Roads Congress does not favour it.
• Speed breakers, where permitted, should be installed, provide visual, audible and tactile stimuli to alert drivers and cause them to slow down. These can have different heights, lengths, spacings, signs, etc. In fact, no particular design is suitable for all the types of vehicles using the road. For example, a speed breaker designed for trucks can be dangerous to motor cyclists and one designed for motor cyclists will be ineffective for trucks. The design recommended by IRC is a compromise design to suit the average Indian road traffic conditions and is based on field investigations and research as shown in the diagram as follows.
Speed breakers are not intended as a substitute for proper mandatory, warning or informatory signs but are meant only to draw the attention of drivers to a possible hazard ahead. It is also suggested by the IRC that a record of speed and accident conditions, before and after the installation of speed breakers, should be kept.

Traffic signal preceded by a useless speed breaker

CORRECT DESIGN OF SPEED BREAKERS
The ideal design of speed breakers is formed basically by providing a rounded of 17 m radius, hump of 3.7 m width and a 10 cm height for the preferred advisory crossing speed of 25 km per hour for general traffic.
In certain locations speed breakers may have to be repeated over a section to keep speeds low throughout. More humps may be constructed at regular intervals depending on actual speed of acceleration/deceleration and characteristics of vehicles. The distance between one hump and another may vary from 100 to 120 m.
There should be proper signage and marking so that the drivers can be warned of the presence of speed breakers by posting suitable advance warning signs. The warning signs should be of the design 'HUMP OR ROUGH ROAD' detailed in the IRC-67-1977 'Code of Practice for Road Signs'. The sign should have a definition plate with the words 'SPEED BREAKER' inscribed thereon and should be located 40 m in advance of the first speed breaker. 
The speed breakers should be painted with alternate black and white bands to give additional visual warning. For better night visibility, it is desirable that the markings are in luminous paint/luminous strips. Embedded cat-eyes can also be used to enhance night visibility. 

MAJOR PROBLEMS
Speed-breakers in the city of Kolkata seldom follow any guidelines, posing threats to all commuters. Speed breakers in the city have made driving hazardous for the following reasons:
• Heights much beyond IRC specifications
• Unauthorised constructions by locals
• Mostly unpainted
• No warning signs

GOVERNMENT NOTIFICATIONS AGAINST SPEED BREAKERS
The Ministry of Road Transport and Highways, Government of India, also strongly discourages the construction of speed breakers on highways. The circular dated 11 April 2016 states that ‘It goes against the Ministry’s policy of not providing speed breakers on National Highways. The function of the National Highways is to facilitate through traffic and not hinder it.’
The circular also bans construction of speed breakers on National Highways and clearly states that ‘Speed breakers should not be constructed on National Highways as these defeat the basic objective of providing an obstruction free high speed facility apart from being a safety hazard. Even the putting of rumble strips has been ordered to be approved by the Chief Engineer (National Highways) who will satisfy himself of the requirement.’
It further reiterated the need for submission of positions of the speed breakers so removed by the order.

REMOVAL OF SPEED BREAKERS ON NATIONAL HIGHWAYS
The circular of the Ministry of Road Transport and Highways, Government of India, dated 29 August 2016 specifically stresses the order for ‘Removal of Speed Breakers on National Highways.’
The Ministry's circular reiterates the Ministry's policy that speed breakers should not be constructed on National Highways as these defeat the basic objective of providing an obstruction-free high speed facility, apart from being a safety hazard. The circular recommended provision of properly designed rumble strips at places like approaches to sharp curves on level crossings, congested or accident prone locations etc., where control of speed on National Highways is unavoidable. 
It was also highlighted that rumble strips are being provided indiscriminately and thus directed that the location of such rumble strips shall be approved by the Chief Engineer (National Highways)/appropriate authority in NHAI INH IDCL who will satisfy himself of the requirement. A copy of such approval letters shall be endorsed to the respective Regional Officer of the Ministry. Further, it was requested that the position of removal of speed breakers and approval of location of rumble strips on National Highways should be intimated to the Ministry by 20 April 2016.

These kind of bumps in the middle of busy thorougfares serve no purpose

WEST BENGAL GOVERNMENT RESTRICTS SPEED BREAKERS
A circular issued by the Government of West Bengal, Public Works Department dated 19 March 2019 states, "It is observed that Speed Breakers/Humps are being constructed indiscriminately on different roads without following IRC guidelines. This is undesirable. It is also observed that due to construction of such Speed Breakers/Humps, the roads are getting damaged at these locations.
To avoid such damages and to ensure smooth vehicular movement it is hereby directed that no Speed Breakers/Humps over the roads would be constructed, without getting Departmental concurrence. It is absolutely necessary the proposal be prepared as per IRC guidelines and submitted to the department for concurrence. Engineer-in-Chief & Ex-Officio Secretary, Public Works Department, will act as the authority for according concurrence after receiving the proposal from the concerned Head Quarter Chief Engineer.
However Traffic Safety Measures as required should be taken up on all roads conforming to relevant provisions of IRC Codes/Manuals."

SLOWING DOWN FOREVER 
In spite of the aforesaid restrictions on speed breakers, the unabated construction of illegal speed breakers continues. What should ideally be a traffic calming measure has become a source of inconvenience for drivers and motorists leading to more accidents than preventing them.
It is high time, the authorities take note of the unauthorised speed bumps and stop their illegal constructions. Every accident hammers home the message that the ‘slowing down’ may be forever.