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A CASE STUDY

PASSENGER ERGONOMICS OF PRIVATE COMMUTER BUSES OF KOLKATA

PREPARED BY MURARI MOHAN MANNA ROLL NUMBER 251

ENVIRONMENTAL SYSTEM MANAGEMENT

PRESIDENCY COLLEGE I st YEAR : 2007-08

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ACKNOWLEDGEMENT

• Mr. Arup Biswas : Public Vehicles Department: Kolkata

• Mr. N Das : Public Vehicles Department: Kolkata

• Vast sections of the passenger population who answered all the queries • Bus operators and the unions of various bus routes plying within and around

Kolkata

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INTRODUCTION

The erstwhile capital of British India, Kolkata is one of the major metros of India. It is the busiest city of eastern region of India and caters to a population of more than 4.5 crores. On any given weekday it is a common site to view the commuters jostling with each other for a place on the footboard of the crowded buses which swivel through the road .The communication system consisting of buses, Trams, Private Cars Taxis and Metro Railways constitute the lifeline for communication of the commuters be it for the school. Office, shop to other places of work or just to tramp on the buses for a joyride. But enough heed has not been paid to the basic amenities of these commuters in the buses. There are not even specified guidelines which have been put forth for the interior of the buses be it from the dilapidated windscreen and roofs to the unscientific of the seats and height of the buses .A lot of work has been done to regulate the emission of various obnoxious greenhouse gases from the buses and steps have been taken to restrict them. But when it comes to the concerns regarding the bumpy rides in the buses no significant progress have been encountered. In the following work the author would like to highlight the basic ergonomic faults some of the buses and try to provide some solutions to the problems faced by several commuters like me .

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AIM OF THE STUDY

The present work contains an analysis, from the ergonomic point of view, of the urban public transport of Kolkata, in which diverse aspects and variables related to the comfort and security of the users of this means of transport have been considered. The points evaluated are the access and exit of the transport unit, the ease to arrive at the seats, dimensional access to the seats, and distribution of the seats. Each one of these aspects was related to anthropometrical dimensions of the Kolkata Population. Finally some suggestions appear on the actions to be taken in design terms that surely will contribute to improve the security and the comfort of the users. Special considerations are done taking into account elderly and children populations The aim of study is to get a comprehensive idea of the problems faced by commuters while traveling in buses and the long term effects it may have on them .While preparing this report due attention has also been made from the bus–owners and operators’ point of view. The fare of the private passenger buses has also been taken into consideration while lamenting on the plight of the passengers on the private buses. Considering the fare of the buses it should indisputably be beyond outlook to get the comfort amenities of luxury cruise coaches, but it should always substantially be expected to get minimum levels of comfort without dumping the concerns of safety and security.

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REVIEW OF LITERATURE

From Márquez, Miguel A. et.al.(2001)

The design of transport means has progressed considerably in the last two decades, mainly in the area of the comfort and security of the passengers. In European countries, USA and many others countries there are standards and regulations in order to prevent accidents and to assure the minimum conditions of comfort and safety of users. Users differ in terms of age, stature, weight and mobility, therefore these factors must be considered in order to satisfy the users` requirements. The aspects to evaluate will be determined by the corporal dimensions of the population of users and by their mobility. The extreme cases are represented by those people of greater body size, individuals with physical limitations and specially the senior and young segments of population that by nature are most prone to accidents.

The basic aspects being considered are :-

• Access and exit stairs of the transport units. • Easy of displacement within the unit. • Access to the seats. • Space available in the seat for the user. • Form of the seats and rakes of seat, and the back rest. • Distribution of the seats.

As part of this approach it is necessary to define what is understood by accessibility, disability and reduced as well as to clearly establish the responsibility of offering these services to the community members.

The term "accessibility" is used to define certain characteristics in the quality of urbanisms, constructions and transport that allow any person to make a suitable use of these.

On the other hand, the term "disability" supposes a physical, intellectual or sensorial deficiency, as well as it contemplates a mental disease or ailment that requires medical attention. Such deficiencies, ailments or diseases can be of permanent or transitory character, with objective characteristics that any professional of the medicine can verify.

A person with "reduced mobility" is affected by diverse factors that prevent their mobility and communication with the surroundings: for instance, people with reduced mobility include pregnant women, as well as injured, convalescent, and over weighted passengers, and infants among others

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Passenger Ergonomics :-

It is possible to carry a great number of passengers in public transport units, but in attention to the users comfort and safety, it is necessary to limit the number of passengers in such way that provide the minimum comfort that the users deserve.

The population of users varies in terms of age, size, weight and mobility, making necessary to consider these factors during the design phase. Extreme cases are represented by the population of bigger size, individuals with physical limitations or disabilities, and specially population segments of elderly and children, who are naturally more susceptible to accidents. Sampling of the public transport units :-

The sampling of the transport units allows measuring the pertinent dimensions, from the ergonomic point of view, such as:

• Inner height • Inner Width • Width of the aisle • Width of the individual seats • Height of back rest of the seats • Height of the seat cushion from the unit floor • Gap between seats • Inner length of the unit • Width of the twin seats • Depth of the seat cushion • Separation between the seat back rest and the contiguous chair • Inclination of back rest • Height from the road to the first step of the access or exit stairs • Height of the steps of the access or exit stairs • Track of the steps of the access or exit stairs • Width of the access or exit door

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Anthropometric analysis:-

In the modern world it is impossible to design in terms of average dimensions. It is for that reason that anthropometry plays a capital role in the world of design. In terms of public transport, it is necessary to define the spaces of circulation, access and exit doors, as well as the dimensions of the seats considering the more corpulent people. On the other hand, the dimensions of the smaller people are used to define the height of the seats, height of the superior handles, height of the steps of the access and exit stairs, and finally the height of the last step of these stairs in relation to the road level. It must be added that public transport is also used by elderly population and people with physical disability, which forces to make certain considerations to facilitate the access, the security and the comfort of these segments of the population during the use of the public transport.

A detailed observation of the statistical data obtained, shows a great dispersion of the data values of the considered variables. The main reason, to which this dispersion of the data can be attributed, is the lack of control by the corresponding authorities as far as construction and distribution of the seats, space distribution and circulation of the users inside the units of public transport; giving freedom of action to the proprietors. There is not control on satisfying the minimum requirements of design according to security standards and the comfort of the users.

Dimensions of transport units were compared with the anthropometric data available of the population of users and the established values in the corresponding standard. Access and exit stairs:- All the passengers must pass through the access and exit doors, therefore it is required that its dimensions satisfy the 95 % of the population.

Users are forced to assume awkward postures and are exposed to risk when getting on to and exiting of the transport units. The inappropriate dimensions of the steps, specifically when these are very high, increase difficulty during the access to the transport unit, especially for the people of short stature, elderly and children. In addition, at the moment of descending from the transport unit, the risks of falling are even greater due to the unstable posture in which the users find themselves.

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Seats dimensions:- In order to evaluate the seats it is necessary to consider, in some cases, the

segments of taller and bigger sized population, for example when evaluating the space available for the legs on seated position; and for others, the section of smaller population, for example for the height of the seats.

Once again the average dimensions are not very elevated in comparison with the values recommended in relation to the back-knee height of the population of users, however, a great dispersion of the data and maximum values, which are very far from satisfying the conditions of comfort of the users, are observed.

In terms of the available space to accommodate the legs in the seated position, it was compared with the anthropometric dimension corresponding to the length from the gluteus to the front of the knee when seated, considering the higher segment of population. It is possible to observe that average values do not fulfill the minimum requirements of comfort to accommodate the legs in the available space, as .Further more, minimum dimensions found during this work are so small that do not allow an adult user to fit in the seat.

When this dimension is very small the main problem that appears is the contact between the knee and the rigid surface of back rest of front seat, which causes pain and annoyance to the passenger. Finally, in the case of abrupt braking or vibrations product of the irregularities of the road, the knee is subject to continuous blows. Some times the space available for the legs is so small; that the passenger cannot place his legs in there causing greater discomfort.

Another dimension of the seat that is of extreme importance as far as the comfort requirements is the width of the seats. It was possible to observe that usually the seats are designed to lodge two people and some times six –seven therefore the analysis has been done based on the space available for each passenger.

It is possible to observe that the average values of this dimension in the seats are far from satisfying the necessities of comfort related to necessary space for the users. One of the consequences is the fact that the passengers must travel tight to others invading the individual space, causing physical and psychological annoyance. In addition, the passenger who seats near the corridor interrupts the circulation and standing passengers and constantly struck by the passengers in transit.

The last set of variables to be considered in the present evaluation is the back rest and seat cushion angles. For the horizontal surface of the seat a backwards inclination angle is recommended, which inhibits the sliding of the individual due to the effects of the braking. As far as the back rest of the seat backward inclination is recommended, this contributes to the comfort of the user.

The horizontal surface and back rest of the seats, are inferior to the recommended values, bringing annoyance and lack of security for the passengers, since the angles do not prevent the sliding forward in the case of abrupt braking. Also, the inclination of back rests forces the passenger to travel in a very unnatural position, causing fatigue and annoyance.

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METHODS AND MATERIALS

���� General Observation:-

Passengers vary according to age, sex, stature, weight, mobility, physical stability, therefore these factors must be considered in order to satisfy the users` requirements. The aspects to evaluate will be determined by the corporal dimensions of the population of passengers and by their mobility. The extreme cases are represented by those people of greater body size, individuals with physical limitations and specially the senior and young segments of population that by nature are most susceptible to injuries and physical and mental discomfort and annoyance.

• Seating:-The Seats of most Public vehicles are unscientific and are a source of great annoyance and discomfort to most of the passengers. Passengers are forced to seat on the crumby dilapidated wooden seats of the vehicles with nil hip, waist, shoulder or elbow room. There are no inclination of the seat which is either straight or steeply ends with the straight wooden panel of the window causing great discomfort to the back.

There are no guidelines for the depth of cushion, inclination of the seat, seat-cover and height of seats in Private buses, so passengers have to bear the brunt of these unscientific designs of the vehicles. Many Rexene-covered seats are inclined forwards causing the passengers to lean forward and slip off the seats on and off.

The height of the seats are also a matter of concern in case of the short stature female passengers who find it considerably difficult to access the seats and has a natural tendency to slide off the seats as their feet does not contact properly with the floor of the bus.

The widths of the two seated chair seats are also too short in length to accommodate the buttocks of two adult passengers.

The passengers are made to sit with their backs facing the windows and their thoracic and lumbar regions are constantly irritated due to complete absence for provisions of any types of backrest. During braking the passengers are constantly jerked to the wooden windows’ clips and there is tremendous discomfort to the thoracic and lumbar regions. After an hour journey in the bus, passengers are completely tattered out.

• Leg-Space: - The provision for leg space as specified by the competent authority (Public Vehicles Department) is only 11 inches, which is rather insufficient for a vast population of the Kolkata passengers. The

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comparatively tall male passengers find it find it considerably difficult to accommodate their legs in the rather short gap. To add to this rather crumbling tale, most buses even fail to comply with the meager 11inches stipulated leg space adding more sorrow to the rather helpless passenger.

• Height of the Unit:-As specified by the PVD the height is only 6 feet. The

average height of the urban male population of Kolkata is about 5’8”-5’10”.The approximate shoe height is about 2 inches. So befitting with the present benchmark height the standing passengers find it considerably difficult to stand erect in proper scientific way. Most of the tall passengers are observed to stand in crumbling conditions with bent back and head.

• Access to the Entry and Exit doors: - The steps of the doors are THREE

staired and they are not quite easily accessible to a vast section of the passenger population due to their unusual height .The aged, disabled, children and women find it considerably tough to enter or exit from the bus.

The steps are also not illuminated at night causing lot of problems during night rush hours due to chances of accidents. The designs of the steps are also quite unscientific.

The grips on the handlebars are completely absent reducing frictions between the palms and the handles, thus posing enormous threats of causing accidents. In general observations it has been noticed that a major significant fatalities on city streets are caused due to slip of palms from the handrails of the bus doors. The widths of the doors are also narrow for alighting of comparatively flabby persons.

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���� Questionnaires:-

A] To the passengers- ���� Are you a daily passenger of the private bus?

���� What is your age?

���� For how many years you are travelling on the particular route?

���� Approximately how much time you have to spend in the bus?

���� Which time of the day you generally ply on bus?

� Does your head touch the ceiling of the vehicle when you stand

erect?

���� � In a crowded bus do you have enough support to balance yourself?

���� Fortunately if you get a seat, can you fit your buttocks completely in

the seat?

���� While being in the seat can you flex your body without causing annoyance to

co-passengers?

���� Are you etched in the back due to absence of any type of backrest?

���� Do you have enough legroom between the seats to keep your legs in the right

position?

���� Do you have discomfort in your legs for cramping the legs for a long time?

���� Do you think that the heights of the seats are too high to support the foot?

���� Even during mild braking do you feel that you are being thrown off or slided

off your seats?

���� Do you have problems with the illumination level within the vehicle while

traveling at night?

���� Do you have problems with the height of the steps while alighting or when

descending from the vehicles?

���� Do you think that the widths of the doors are reasonable for proper entry and

exit?

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���� Do you think it would have been better if there had been lighting facilities in

the steps?

���� Do you have pain in the thoraco-lumbar region after sitting around 20 minutes

in awkward position in the bus?

���� If you have traveled in other city buses how would you compare the level of

passenger satisfaction in respect of comfort and security in other cities and our

private buses while taking in consideration the fare?

���� Finally what suggestions do you wish to convey to improve the quality of

travel by bus?

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B] To the Authorities of Public Vehicles Department –

���� What factors are taken into consideration while issuing permits to the

vehicles to be roadworthy?

���� After how many days are the permits of the vehicles reviewed? ���� What should be the height between the floor and ceiling of the vehicle for the

passenger to stand?

���� How are the numbers of seats in buses determined?

���� What should be the gap between seats for the Leg-Space?

���� What should be the height of the seat cushion from the unit floor?

���� What should be the depth of the seat cushion and inclination of the seats?

���� What should be the maximum height of the seat from the floor?

���� What are the provisions for the inclination of the Back-Rest?

���� What should be the width of the seats?

���� What should be the covering of the seats be of?

���� What should be the width of the access and exit doors?

���� What should be the dimensions of the access and exit doors of the vehicle?

���� What are the specifications for the lighting system within the vehicle?

���� Is there are provisions for lighting the steps?

���� Are there any specifications for arrangement of the handrails for the standing

passengers?

���� Are there any specifications for gripping the hand rails of the doors?

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RESULTS AND FINDINGS ���� Observations:-

After an extensive survey on the city buses for several months it has been noticed that the plight of the passengers are generally overlooked in the sections of safety,comfort,security and ergonomic suitability of the vehicle. The rules laid down by the Public Vehicles Department for implementation on the private buses are not up to the mark in relation to other countries and even there are not any specified benchmarks on certain aspects. The bus operators and proprietors still care a fig to the existing rules and ply the buses while putting the concerns of the passengers at stake.The plight of the elderly citizens, children and women are more painful.

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���� People’s Reaction – Reactions of the passengers are given below in the tabular form:-

Male

Female

No Questions

Yes No Non- Respondent

Yes No Non -Respondent

1 Does your head touch the ceiling of the vehicle when you stand erect?

17 13 - 4 26

2 In a crowded bus do you have enough support in form of rods to balance yourself?

30 0 - 30 0 -

3 Are you etched in the back due to absence of any type of backrest?

25 4 1 28 1 1

4 If you get a seat, can you fit your buttocks completely in the seat?

5 22 3 2 19 9

5 While being in the seat can you flex your body without causing annoyance to co-passengers?

7 22 1 2 17 11

6 Do you have enough legroom between the seats to keep your legs in the right position?

13 15 2 18 10 2

7 Do you have discomfort in your legs for cramping the legs for a long time?

25 5 - 25 2 3

8 Even during mild braking do you feel that you are being thrown off or slide off your seats?

20 5 5 26 2 2

9 Do your feet touch the floor of the vehicle when you are seated?

22 6 2 11 19 -

10 Do you have problems with the illumination level within the vehicle while traveling at night?

10 19 1 19 11 -

11 Do you have problems with the height of the steps while alighting or when descending from the vehicles?

4 25 1 22 7 1

12 Do you think that the widths of the doors are reasonable for proper entry and exit?

26 4 - 24 4 2

13 Do you think it would have been better if there had been lighting facilities in the steps?

30 - - 30 - -

14 Do you have pain in the thoraco-lumbar region after sitting around 20 minutes in awkward position in the bus?

4 17 9 10 15 5

15 Do you have any symptoms of spondylosis or back pain owing to traveling in the private buses for years?

12 16 2 15 5 3

NOTE:-The survey has been carried out among 30 male and 30 female daily passengers between Jan-May 2008.

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���� Reaction of Public Vehicles Department-

[Excerpts from the interview with Mr. N Das (Asst.Director Technical; Public Vehicles Deptt. Govt of West Bengal) and

Mr.Arup Biswas (Engineer, Public Vehicles Deptt. Government of West Bengal)]

���� What factors are taken into consideration while issuing permits to the vehicles to be roadworthy? Several factors are taken into consideration while taking into view of the roadworthiness of the vehicle like condition of the outer surface of the vehicle, headlight, tail-light, functionability of the windscreen wiper, speedometer, condition of the glass and wooden windowpanes, seats, accessibility of entry and exit to the vehicle, clearance certificate from the State Pollution Control Board, functionabiliy of the horns and design of the vehicle.

���� After how many days are the permits of the vehicles reviewed?

A new vehicle is given no objection certificate for the initial two years and they are subsequently reviewed after every one year and issued no objection certificate after thorough inspection of the vehicle.

���� What should be the standing height of the vehicle?

The rule states that the height of the vehicles should be six feet.

���� Is not six feet insufficient for the Kolkata population? Should not the rulebook emphasize on increasing the height of the buses? The height may be insufficient for some individuals but the rule could not be lenient for that small percentage of the population. Some buses may have increased height of about 6`4”for the benefit of the tall individuals but the PVD cannot implicate any bus for being six feet in height.

���� How are the numbers of seats in buses determined?

The total numbers of seats in private buses are determined on the basis of the length of the WHEEL-BASE i.e. the distance between the lengths off the wheel. In general the specified numbers of seats in Private buses are 38+1.

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���� What are the rules regarding width of individual seats?

Seats are dimensioned allotting 15 inches space to each seated individual. So, for a twin seated seat the width should be 30inches and for six seater it should be 90 inches.

���� What should be the gap between seats for the Leg-Space? 11inches space is the specified rule.

���� What should be the height of the seat cushion from the unit floor?

There are no specified guidelines.

���� What should be the depth of the seat cushion and inclination of the seats? There are no specified rules.

���� What are the provisions for the inclination of the Back-Rest?

The are no provisions for backrest in the older wooden bench structure of the

seats permitted on the roads before 2003 but the newer vehicles permitted after 2003 where most of the seats are chair seated with twin sharing basis have provisions for backrest but there are no stipulated inclination guidelines.

���� What should be the covering of the seats?

There is no specified guiding principle for the outermost cover of the seats.

In most cases it is of Rexene.

���� What should be the width of the access and exit doors?

The width of the door should be 16 inches.

���� What should be the dimensions of the access and exit doors of the vehicle? There should be three steps. The lowest rung step should be at a maximum height of 15 inches from the ground and the next higher steps should be at a maximum height of 9inches and 9inches respectively.

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FIRST STEP (Ground Clearance) 15 inches

SECOND STEP (From Ist Step) 09 inches THIRD STEP (From 2nd Step) 09 inches ���� What are the specifications for lighting within the vehicle? There are not any specified rules regarding lighting within the vehicle.it depends upon the bus body builders for the type of lighting. ���� Is there are provisions for lighting the steps? There are no guidelines for provisions of lighting the steps in the older vehicles. ���� Are there any specifications for arrangement of the handrails for the standing passengers? There are no specific rules; it is done mainly by the Body Makers of the buses on conventional basis.

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���� Actual Findings- During the elaborate survey it has been found to the dismay of the author that large sections of the Private Buses flout the even lenient norms set by the Public Vehicles Department and ply endangering the security and comfort of large sections of the population. A tabular representation of the ergonomic state of the vehicles are given henceforth-

NOTE: - The survey has been carried on 30 vehicles plying on various routes randomly

No Variable Feature PVD Standard (inches)

Observed Average (inches)

Standard Deviation

Maximum (inches)

Minimum (inches)

1 Inner height of the Vehicle 72 71.5 0.353 74 70.5 2 Width of six sitter seats 90 86.75 2.298 91 82 3 Width of twin seats 30 27.5 1.767 31 25.8 4 Depth of the seat cushion - 1 1.5 0.5 5 Height of the seat from the

floor 16 18 1.414 19 14.5

6 Legroom between seats 11 9.75 0.884 12 7 7 Inclination of the backrest of

twin seats - 10.5O 18O 7.5O

8 Height from the road to the first step of the access or exit

stairs

15 16.5 1.060 18 14.5

9 Height of the steps of the access or exit stairs

9 9.7 0.495 10 8.7

10 Width of the access and exit doors

16 15.75 0.177 17 15.5

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CONCLUSION AND SUGGESTIONS

It has been concluded from the project that the city private buses ply without paying much attention to the ergonomic design and the safety and security of the passengers. The enforcing authority (Public Vehicles Department) is also quite lenient in structuring of the ergonomic rules for the Private buses .It has also been observed that in several Variables have no specified guidelines like the depth of the seat cushion, inclination of the backrest, lighting facilities within the unit nature of the cover of the seat. Even the meager laws are flouted widely by the bus operators. Additional factors such as service, value, comfort, and psychological and social costs can also influence travel behavior and have not been adequately explored, nor have their relationships to travel satisfaction adequately been investigated. Not only are bus services poor, but also access to them in terms of capacity is deplorable, making the use of auto rickshaws also a necessary. Realistically, it may not be possible to offer the standards that exist in the developed countries initially but they must be gradually upgraded as travel begins to play a much bigger role in transporting more people . Traveling by private buses must be preferred to smaller as they carry more individuals thus consuming less fuel per capita travel per kilometer and thus preventing less green house gas emission compared to private cars and auto rickshaws.

A complete lack of satisfaction of the minimum requirements of the population of users in terms of its corporal dimensions is observed. This indicates the necessity for redesign of the units of public transport, in which the anthropometric dimensions of the population of users must be considered. A lack of consideration towards the segment of population of children, senior and people with physical disabilities of diverse nature are observed in the design of public transport units.

Some feasible ergonomic upgradations which can be made keeping in view

the comparatively low fare structure pf the private buses are as follows:- • The steps of the units should be made 4 staired.

• The height of the first step from the road should not be more than 10 inches

instead of the present 15 inches and that of the consecutive steps should be 6

inches instead of 9 inches.

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• There should be facilities for lighting the steps.

• The inner space within the unit should be well illuminated.

• The hand rails of the stairs should be gripped for proper gripping during

entry and exit to prevent accidental falling.

• The footboards should be sturdy

• The seats should be of twin sharing basis and should be front. faced.

• The flexibility of the seat cushion should be minimum of 5 inches even after

seating.

• The seats should be covered with cloths to prevent sliding.

• The width of the twin sharing seats should be minimum 32 inches.

• The inner height of the vehicle should be minimum of 6’2”.

• The height of the upper head rods should be lowered for the region of female

passengers and should be provided with clasping belts.

• The legroom between seats should be a minimum of 13 inches for proper

flexing of the legs and not to hurt the knees while flexing forward or

backwards.

• The height of the seats should be 15 inches from the floor of the vehicle

• If possible facilities for proper ventilation should be made.

• Moreover the ergonomic laws should be applied more stringently by the

competent authorities and steps should be taken for proper surveillance

before issuance of certificates for the vehicles to be road worthy.

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ALBUM

Broken and dilapidated footboard Missing window pane

Insufficient legroom space Sitting in crammed position

Height of seats too high for the feet to No backrest – thoraco lumbar region unsupported touch floor

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The nature and quality of seats

Passengers vying for support to balance in a crowded bus

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Different positions assumed by different ages of population while alighting the bus

Buses stranded in Esplanade Stand

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