Railways rope in Sensors, Lasers, Laptops to analyse the gap between train footboard and platform – rules out raising every platform to 920mm at all the stations
With the number of people losing their limbs and lives after falling into the gap between the train footboard and the platform increasing, the Bombay high court had asked the railways to check the feasibility of raising platform height to 920 mm. The authorities have finally taken up the task of arresting the menace.
Officials of the Western and Central Railway, along with experts from the Research Design Standards Organisation (RDSO) – the railway’s apex technical authority – carried out a trial using laser-controlled sensors and computers to find a solution to the platform gap problem. The trial started at 11pm on Tuesday night and went on till 2am on Wednesday. The three-hour long drive, however, gave out a mixed verdict. A section of railway officials clear in their position that raising the height of platforms beyond 900mm or 920mm would be dangerous rather than safe.
The Research, Designs and Standards Organisation (RDSO), the suburban railway and an HC-appointed team of citizens undertook trials from Monday that involved the MRVC rakes and the old retro-fitted rakes to ascertain the ideal platform height.
“We decided to take the readings of the lateral and vertical movements of the trains at 70 kmph speed at platforms at 920 mm height,” a senior official said.
Not all platforms on the suburban railway network will be raised to a height of 920 mm. Trial runs with different types of rakes over the past two days have ruled out a blanket increase in height to this level. Ideally, there should be a margin of 150 mm between the footboard of the train and the surface if the height of the platform is up to 840 mm. If the height is allowed to go up to 920 mm, the margin can be maintained at 50 mm if there is no compromise on maintenance of tracks and coaches.
“A rake whose air springs fail should be withdrawn from service as it can push down the coach and lead to collision with the platform,” the official said. “This may lead to the amputation of legs of people standing on the footboard or head injuries due to a fall from the train.”
On Monday, a 30-40 mm gap was observed on Platform No. 6 at Andheri station when MRVC rakes with fully loaded coaches were used. On Tuesday, when older rakes were used, sensors fixed beneath the footboard grazed the surface of the platform at Elphinstone Road. At Charni Road, where work was is in progress to increase the platform height, the platform surface was hit. The height was found to be 970 mm but was to be reduced to 920 mm eventually. “This proves that height can’t go beyond 920 mm,” the official said.
Another official said that the height would definitely be increased beyond 840 mm to prevent mishaps, but it may ultimately vary from 900 mm to 920 mm. “But all platforms cannot have a uniform height of 920 mm because things like the topography and the design of the platform [curvatures] may vary,” the official said.
The trails were carried out with 12-car trains at 70 kmph speed on WR. MRVC rakes with air springs and old rakes with coil springs, both were used on separate days. While one unit was fully loaded to super dense crush load capacity with sand bags, one was partially loaded with men, while the last was one was empty. Unlike rakes MRVC rakes, old Rakes with coil springs get pushed down due to over-loading. Sensors were fitted beneath the footboard of each coach to measure the gap as the train passes by the platform.
Laser and computer trial
It involved attaching sensors, controlled by lasers, to two coaches of a retrofitted old train.
The 12 sensors, six each around the two coaches, are part of a mechanism where a laser is continuously emitted when the train is in motion. The laser ray hits the base of the platform while the train is on the move and the path travelled by the laser and the time taken gives the reading of the gap between the base of the train and the platform.
These readings, continuously being fed into two computers, were analysed to find out the changes in the gap as the train hurtles towards its destination, moving sideways and vertically along the undulation of the tracks. The train itself was made fit for the journey by filling up some compartments with sands so that some of the coaches achieved a weight of 36 tonnes, the average weight of a coach when it is packed to the brim with commuters.
“This is the most scientific way to do it. The sensors, which can give 100 readings a second, will tell us exactly the measurements of the gap in a dynamic situation, that is when the train is running at a speed of 80 kilometres per hour,” said RK Sharma, additional divisional railway manager, WR.
The journey plan
The plan was to check the few platforms on WR’s suburban route which have been raised to a height of either 920mm or above the stipulated height of 840mm. The train made its journey from Churchgate and on the way checked platform number 1 of Charni Road, Grant Road, Parel, platform numbers 1 and 2 of Elphinstone, platform number 5 of Vile Parle, platform number 4 of Dadar, platform 7 of Andheri station, platform number 5 of Khar and also one at Goregaon station. This, as officials said, was to find out if indeed the city’s platforms can cope with a rise in their heights.
As the train ran at a speed of 80 kmph between Churchgate and Andheri, the logic of raising the platform height – so predominant in the mind the gap debate currently on – was turned on its head once the train pulled into platform number 7 – the Harbour platform – at Andheri station.
Thanks to the height of the platform being raised to 920mm, there was almost no gap between the floor of the train and the platform. “The problem is that once monsoon sets in, the soil beneath the tracks gets loose which in turns sinks the ballast and the tracks. That reduces the gap further. This is a situation where the base of the train can actually hit the edge of the platform while it is entering it,” said Sharma.
The evidence of the railway’s apprehension was in the form of the crushed metal casing of the sensor attached to the base of the coach. Officials believe the case hit the platform possibly at Elphinstone station. The previous night, the casing once again broke as another trial train made its way past platform number 2 of Charni Road station.
“We found that the platform height there was almost 970mm, which is beyond the stipulated limits, and it hit the side of the train,” aid an official.
The road ahead
Late on Monday night, the railways conducted trial with a new Siemens rake which due to air-spring suspensions has a height that is greater than the older BHEL-make rakes. On Tuesday night, the trial was with an older retrofitted rake with coil spring suspension which tend to compress when the train is crowded. A trial with a long-distance coach would be next.
However, according to officials, the toughest part of the trial would be to see if the platforms can be raised to a height of 1,200mm as some independent experts have said during the course of the trial in the High Court.
“That will require placing plants on several platforms to get the height of the platform to 1,200mm. It will inconvenience people because the platforms with such planks would have to be kept closed for long periods,” said an official.
Report of December 5 hinted new rakes leaving a dangerous gap
The new rakes, both Siemens and the two Bomabrdier rakes being trial-tested currently, have heights that are not in confirmation with rules laid down by the railways Schedule of Dimensions.
The rules say that the height of the platform should be anything between 760mm and 840mm from the top of the rails. Under these rules of safety, the maximum gap between the platform and the floor of the train should be between 342mm and 437mm.
For example, the Siemens rakes have a floor height of almost 1,220 mm whereas the ideal, as per railway rules, should be around 1,187mm to 1197mm from the top of the rails. The new Bombardier rake currently stabled at Virar carshed is a touch worse with a floor at a height of 1,230mm from the top of the railways.
But as is evident, the gap even for platforms with a stipulated height of 760mm, when it comes to new rakes, is as large as 470mm, a gap that railway officials agree is dangrous. Over the past couple of years, both the Western Railway and the Central Railway have been increasing the height of its platforms to get them to 840mm but have now realised that even this isn’t safe enough.
Platform raising chart
WR in 2012-13 raised the heights of 6 platforms at Dadar, Kandivli, Malad, Borivli, Bhayander and Virar. It currently has 9 platforms in Grant Road, Charni Road, Elphinstone, Lower Parel, Vile Parle and Khar where work is in progress. Tenders have been awarded for another 20 platforms in Andheri, Jogeshwari, Bhayander, Kandivli, Mumbai Central, Marine Lines, Charni Road, Lower Parel, Mahim, Bandra, Khar and Dadar.
Central Railway: 105 rakes, 40 Siemens, 65 BHEL,
Western Railway: 82 rakes, 65 Siemens, 17 BHEl, 2 Bombardier being tested