Great Western Coffee Shop

...on the urban railway in Gdansk, Poland.
(http://bi.gazeta.pl/im/d7/ae/16/z23784151V,Kadr-z-filmu-zamieszczonego-na-profilu-Polska-w-du.jpg)

Apparently two balloon-sellers managed to get all these dozens helium balloons into the train, where they "filled the entire carriage." They were travelling to the site where they were going to sell them (perhaps the beach, but it doesn't say). I'm not sure whether all the balloons survived the journey unburst – or whether the other passengers' tempers burst.

Of course Polish trains might be long enough to accommodate passengers and bulky luggage, of which balloons could be considered a part.

More concerning is the proximity of balloons to OHLE, presuming that this at 25Kv. An escaped balloon that touches the overhead, but that has the string or cord within reach could end very badly.
As could a large bunch of balloons with the top of the bunch near the overhead.

If people smoke on the trains, then one hopes that the balloons were inflated with  helium rather than hydrogen. Hydrogen is sometimes used for cheapness, and is reasonably safe outdoors but a hazard in enclosed places.

Good point about the OHLE, which is visible in the photo. I don't know what the voltage is; a quick search throws up a Polish electronics forum where someone says it's "3kV 16,2/3 Hz" which sounds quite enough to be potentially* dangerous.

*Pun unintended but I'll leave it.

3Kv DC.

See it's one of the indigenous EN57 EMUs from 1961 to 1993. They rattle and bang their waya round Poland. The last time I travelled on one, the doors started opening as we were running. Some units have been modernised but this an original.

3Kv DC is likely fatal if touched, or poked with a metallic item held in the hand.
In case of a non metallic string or cord attached to a balloon, then 3Kv is lower risk than 25Kv.

Still best avoided though.

I've never seen the doors opening while moving – but I've often seen them fail to close. The warnings to keep away from the doors should be taken seriously!

When I was in Adelaide it was a regular sight to see the commuter trains operating with their sliding doors open. Have a photo somewhere which when I can get round to it I'll hook out, scan and post.

Same on the old Pretoria-Johannesburg, non-air-conditioned commuter stock in the days before the Gautrain. Only way to get the temperature right.

I ended up stuck on the outside of one of those doors once and that got a bit hairy! Dashing for a departing train with an over-sized back-pack.  Ooops  :o

Having seen how the suburban trains in Mumbai were ridden 30 add years ago (door openings simply providing something useful to cling onto) our Polish balloon seller looks like a paragon of health and safety best practice......