When did the platform heights change?

[Mudkip Orange]

If you look at rural stations like the one towards the end of this video, you'll note that while the underlying platform is long - say, 16+ carlengths - and has a lower height, with a shorter raised section that's designer around the shorter/regional trains of today - say, 8 carlengths.

 

Seeing as how the Japanese have always been keen on standardization, when did this height change? You see it all over the old stations of the country and the provincial cities.

[KenS]

Good question.  I have no clue what the answer is.

 

The raised section was clearly added above the original platform (in the video you can see the edge of the old top at the same height as the top of the lower section, underneath the new top).  I'd guess the reason to have both was to allow both kinds of trains to operate for some period.

 

I've never seen this kind of platform height difference in an urban Tokyo station (the kind I mostly look at photos of), so perhaps it was limited to loco-hauled stock or early DMUs.

[to2leo]

I am guessing this but I think the platform height change might be started when JR decides to use DMUs and EMUs since the motor needs to fit below the floor.  It might also due to easy embarking and disembarking and increasing wealth to do high platforms.

[bikkuri bahn]

Back when most trains were loco-hauled (especially outside of the big conurbations), the platform heights above the rail level were 760mm.  With the widespread use of commuter and suburban EMUs, the platform height was raised to 1100mm on those station platforms served exclusively by such trains.  For those platforms served by loco hauled trains, DMU's and certain ltd. express stock with single steps, as well as aforementioned commuter stock, an intermediate height of 920mm is the standard.  Likely, as 2leo mentioned, the EMUs require the higher platform due to the floor levels being higher to accommodate the underfloor electrical equipment.  Also, the EMUs have no steps to speed passenger boarding and thus reduce station dwell time.  That said, it seems some (at least to my eyes) of the newer EMU units used in Tohoku have lower floors to reduce the height gap when using those lower platforms common on the rural stations.

[marknewton]

That's some useful information on platform heights, BB - thanks!

 

Cheers,

 

Mark.