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Back up for Air Con / Heat

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kermit

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When trains with air conditioning break down, or are deprived of their power supply, a frequently heard (and legitimate) passenger complaint is that the atmosphere on board can quickly become oppressive and unpleasant.

This is not an unforseeable scenario.

How hard can it be for contingency plans for some form of ventilation to be built in - or even, in winter, some emergency heating options (a chimney hatch for a pot belly stove is my favourite idea for this so far, but I can see that the technologists might have moved on.....)?
 
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Bletchleyite

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Many (if not all) of Southern's Electrostars have a few opening windows (locked using a T-key) per coach for this scenario, and on the BBC's pictures you can see them open. But when the train is stationary on a hot day, even a full set of opening windows won't cool a stationary train adequately.
 

Domh245

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I'd be interested to see what solutions you propose for a train that has become stranded without power (as happened this morning). You'd either need to get passengers operating bellows or generating backup power (cycle machine?) to power any HVAC system fitted to a train.

What needs to be focused on is the ability to sort problems out quickly and getting passengers off trains that are stranded quickly, as there is no realistic way to retrofit a completely passive ventilation system onto a train
 

kermit

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I'd be interested to see what solutions you propose for a train that has become stranded without power (as happened this morning). You'd either need to get passengers operating bellows or generating backup power (cycle machine?) to power any HVAC system fitted to a train.

What needs to be focused on is the ability to sort problems out quickly and getting passengers off trains that are stranded quickly, as there is no realistic way to retrofit a completely passive ventilation system onto a train

Whilst the wish for a speedy resolution is sensible, we know it doesn't always happen.

Air con is power hungry, so practical solutions need to be based on fresh air ventilation, either variants on the Mk 1 window (a design classic - how does the wording go again? "For draught-free ventilation...."), or an option for battery powered lightweight energy efficient forced ventilation of some sort. Passengers stuck next to a toilet on a hermetically sealed broken down Voyager would have an excellent legal case IMHO, for punitive and exemplary damages..

The damage may indeed have been done with much of the stock currently on the rails, but it doesn't seem unreasonable to expect anything new to have this problem addressed in the spec.
 

chris11256

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I was told by c2c's MD at a recent passenger panel that onboard batteries will keep aircon running for an hour following power loss. Beyond that he said it's company policy to ensure passengers aren't stuck onboard for longer.
 

LAX54

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It used to be that in such events, (at least on hauled stock) the sliding doors at each end of the coach to be kept open, and all the door windows opened in the vestibules, not ideal, but I assume better than nothing !
 

kermit

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I was told by c2c's MD at a recent passenger panel that onboard batteries will keep aircon running for an hour following power loss. Beyond that he said it's company policy to ensure passengers aren't stuck onboard for longer.

A very nice aspiration (no pun intended), but when policy meets reality passengers suffer. Should there be a lower-power battery conservation mode available to on train staff when delays seem likely to exceed an hour?

Or, as mentioned above, the option to open some windows or vents?
 

hassaanhc

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A very nice aspiration (no pun intended), but when policy meets reality passengers suffer. Should there be a lower-power battery conservation mode available to on train staff when delays seem likely to exceed an hour?

Or, as mentioned above, the option to open some windows or vents?

The c2c Class 357 Electrostars don't have emergency window hoppers, unlike the Southern and Southeastern ones. And I'd be shocked if the battery could power air conditioning for anywhere near an hour.
 

table38

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Maybe on 1/3 2/3 door stock, it would help if the doors could be opened manually to leave a gap (but not large enough to fall through!) via some "non-emergency" manual release to be operated by the guard?

Although I remember once being stuck sweltering on a plane for a few hours, and the staff opened the doors, then the people near the doors complained they were too cold!
 

route:oxford

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When trains with air conditioning break down, or are deprived of their power supply, a frequently heard (and legitimate) passenger complaint is that the atmosphere on board can quickly become oppressive and unpleasant.

This is not an unforseeable scenario.

How hard can it be for contingency plans for some form of ventilation to be built in - or even, in winter, some emergency heating options (a chimney hatch for a pot belly stove is my favourite idea for this so far, but I can see that the technologists might have moved on.....)?

You just design a unit to have a small diesel generator to supply hotel power if the knitting comes down.

Then have militant rail enthusiasts complain that about it either lugging around unnecessary equipment or complaining that the throb of the generator was ruining their enjoyment of suffering a breakdown on a rare bit of track.
 

DarloRich

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Maybe on 1/3 2/3 door stock, it would help if the doors could be opened manually to leave a gap (but not large enough to fall through!) via some "non-emergency" manual release to be operated by the guard?

Although I remember once being stuck sweltering on a plane for a few hours, and the staff opened the doors, then the people near the doors complained they were too cold!

the problem is someone will force the doors and bail out.

As an aside it gets extremely uncomfortable very quickly on a stuck tube train and there is little they can do to aid ventilation
 

table38

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the problem is someone will force the doors and bail out.

But what's to stop them operating the "real-emergency" release and doing that anyway?

As an aside it gets extremely uncomfortable very quickly on a stuck tube train and there is little they can do to aid ventilation

True enough, but not a reason to do nothing for surface stock (or even Tube stock when not in a tube :))
 

DarloRich

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But what's to stop them operating the "real-emergency" release and doing that anyway?

Nothing - other than they haven't, until that point, seen anyone else undertake the action. There is s till a mental line the person has to cross to undertake the action of opening the doors



True enough, but not a reason to do nothing for surface stock (or even Tube stock when not in a tube :))

I think i was trying to say that the only time i have ever been really uncomfortable (heat wise) on a train in the UK is in a tube train stuck in a tunnel.
 

edwin_m

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In the RAIB report on the stranding of a Thameslink train a few years back, it was mentioned that their 319s had a safety barrier which could be set up behind a door so it could be opened for ventilation on a stranded train with no risk of someone accidentally falling out.

I'm currently involved in the design of a Metro where one of the key requirements is to be able to get everybody to safety in the limited time the aircon will keep running if the power fails. This is on a viaduct in a country where the temperature can tough 75 degrees.
 

table38

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Nothing - other than they haven't, until that point, seen anyone else undertake the action. There is s till a mental line the person has to cross to undertake the action of opening the doors

Or, maybe with a bit of ventilation, they'd be less inclined to take the obvious alternative which would be to operate the emergency release which would allow the doors to open fully (and risk falling out) :)
 

DarloRich

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Or, maybe with a bit of ventilation, they'd be less inclined to take the obvious alternative which would be to operate the emergency release which would allow the doors to open fully (and risk falling out) :)

maybe - but i dont trust people ;)
 

table38

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maybe - but i dont trust people ;)

Heh, me neither :) On the plane, there were sufficient stewards to man person the doors to stop people falling out. Maybe the TOCs should recruit some regular commuters as voluntary "train marshals" to subjugate any passengers who look likely to start using their own initiative :)
 

Pigeon

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Air con is power hungry, so practical solutions need to be based on fresh air ventilation, either variants on the Mk 1 window (a design classic - how does the wording go again? "For draught-free ventilation...."), or an option for battery powered lightweight energy efficient forced ventilation of some sort. Passengers stuck next to a toilet on a hermetically sealed broken down Voyager would have an excellent legal case IMHO, for punitive and exemplary damages.

Or, indeed, for smashing the windows, as has been known to happen.

The Underground has strict standards for trains stuck in tunnels and how long you're allowed to mess around trying to get them moving again before you have to give up and evacuate them, to avoid passengers suffering from heatstroke. For sure the Underground is something of a special case, but it's still possible for the risk of heatstroke to arise on the "proper" railway; it is a potentially life-threatening condition and it's just not on to hope it won't happen.

No need for any fancy technical solution involving batteries or generators, that's just overcomplication to the point of daftness. Opening windows, and plenty of them, is the answer - they should never have got rid of them in the first place.
 

tsr

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Southern have an on-train Hot Weather Policy, which includes both opening the hopper windows, and also the use of emergency mesh barriers attached to handrails by the passenger doors. The doors are opened by means of the standard emergency egress handles, and the barriers erected. The doors are then powered down to turn off the hustle alarms and left open, but they must remain manned by a competent member of staff or volunteer in order to prevent trespassing. This applies to every door for which a volunteer and barrier can be sourced. There are also guidelines for which doors should be opened for maximum airflow. And yes, as above, the gangway doors will be locked open. In the event of a fire, a high priority action will then be to close those doors as needed.

Unfortunately the Hot Weather Policy being implemented will usually result in a line block and traction current isolation on the side of the stranded train where the doors are open, which can cause quite a lot of disruption until a rescue is effected. However, in the case of the Clapham Junction incident yesterday, I'm not sure yet whether it was practical to use the mesh barriers or whether that was done. As the incident was on the Up Fast, it should have been possible to open some doors without a line block on any adjacent line (though in practice this would have been in place anyway, I believe).
 
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theageofthetra

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If you took an average 4/5 car unit what sort of size diesel/gas turbine Gen set would you need to keep modern batteries topped up to provide many hours of 'hotel' power. There is plenty of spare space under some carriages surely something could be fitted to keep all essential systems working.
 

AM9

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....but it's still possible for the risk of heatstroke to arise on the "proper" railway; it is a potentially life-threatening condition and it's just not on to hope it won't happen.

Nobody wishes for it but one day there might be a death of an individual with an intolerance of extreme heat conditions. All hell will then be let loose (ooops, sorry about the pun). Not only will the media, MPs, medical commentators, anti-rail types et al have a field day, but the next time there is a similar passenger 'lock-in', far less than yesterday's mess, some passengers will assume the roles of near-to-death victims or their saviours and window breaking will 'break out' everywhere. The tide will be unstoppable.
Apologies for the number of colloquial phrases.
 

W230

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Heh, me neither :) On the plane, there were sufficient stewards to man person the doors to stop people falling out. Maybe the TOCs should recruit some regular commuters as voluntary "train marshals" to subjugate any passengers who look likely to start using their own initiative :)
Believe it or not this is what we are now instructed to do if we have another 1W95 (Kentish Town) incident. We now have door barriers tucked away on the 377s (and presumably 387s) to pop open the doors, fit them and let the fresh air in, finally asking upstanding members of the public to police them. Whether it would work next time we need to do it of course...

I do admit that a train could very quickly become uncomfortable on a nice sunny day packed full of people though I am more cynical in how "uncomfortable" some of these trains are that end up trapped at other inclement times. And uncomfortable is not dangerous either, it's uncomfortable. Saying that I am in no way defending the ridiculous length of time some of these incidents are taking to resolve.
 

broadgage

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I was told by c2c's MD at a recent passenger panel that onboard batteries will keep aircon running for an hour following power loss. Beyond that he said it's company policy to ensure passengers aren't stuck onboard for longer.

I very much doubt that proper air conditioning that actually refrigerates air to a lower than outside temperature could be run from batteries.

Forced air ventilation that merely replaces the inside air with outside air uses much less power and could be powered from batteries, and is perhaps what is being referred to by c2c above.
Forced air ventilation is a poor substitute for proper air conditioning, but is certainly better than nothing.
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If you took an average 4/5 car unit what sort of size diesel/gas turbine Gen set would you need to keep modern batteries topped up to provide many hours of 'hotel' power. There is plenty of spare space under some carriages surely something could be fitted to keep all essential systems working.

It would be about the size of a larger DMU engine, note for example that the nominally electric IEP ARE being fitted with diesel engines to provide hotel power, and also to move the units at a much reduced speed under diesel power.

I rather doubt that it would be feasible to retrofit to existing stock though.

What might be worth considering would to build additional vehicles that DO incorporate a diesel engine and to add these vehicles to existing EMUs that need lengthening. Expensive no doubt, but it would help with both overcrowding and providing emergency power.
 

kermit

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man person

Man can be used as a verb, person can't.

Try Staff.

Anyway, fans without refrigeration, Mk 1 windows, doors that can open a bit (but no more), and pot bellied stoves for winter.

Sorted.

Next!
 

edwin_m

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If you took an average 4/5 car unit what sort of size diesel/gas turbine Gen set would you need to keep modern batteries topped up to provide many hours of 'hotel' power. There is plenty of spare space under some carriages surely something could be fitted to keep all essential systems working.

This and its fuel supply would also be a potential fire hazard which would raise safety concerns particularly in some tunnels.
 
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