Hmmm, I still think it's more than desirables, sorry. And you can't produce any evidence either. Other fora seem to think this way too.
I think I can see how that's gone now - yet hasn't really.
Originally just one safety requirement specifically about passenger trains came from the concession:
(ii) Except where operating rules otherwise permit, all trains shall be equipped with two
locomotives, one situated at the head and the other at the rear of the train enabling the train to
be split and to reverse direction. This arrangement may be modified for certain types of trains
(particularly in the case of freight trains) and in certain operating conditions provided that the
operating rules are followed.
- and even that is secondary to Eurotunnel's operating rules.
The rest were a matter of Eurotunnel alone, or Eurostar in negotiation with them, proposing safety rules to the IGC (Intergovernmental Commission). The IGC approved those based on advice from their safety advisers, and the resulting rules were not, I'm pretty sure, published.
Since then the legal framework has changed because of domestic changes in Britain and France, and a bigger one with the introduction of the European Railway Agency and the TSIs. At the same time, the IGC held a review and consultation about the operating experience and whether all the rules were needed, during which Eurostar and other operators (
DB» ) started asking if they could other trains, even ones not designed specifically for the tunnel.
The IGC came out with
their conclusions in 2010, removing some requirements. They notified the ERA, who decided to
respond to that (in 2011) as an enquiry about its compatibility with the TSIs. It isn't clear if there has been an further change by the IGC in response to the ERA.
The general trend in these safety regimes has been to get less prescriptive, and rely more on applicants making a safety case to be approved against a set of principles. In railways this involved applying the "Common Safety Methods" in a risk assessment. So while Eurotunnel do still put the conditions for access in their Network Statements, the safety rules are only referred to, and even may have fewer fixed rules.
The contentious rules about minimum length and end to end gangways are there for one reason: to allow evacuation via one or two doors close to a cross-passageway where the tunnel is full of smoke (or other similar hazards). They were "normally required" before to provide "the optimum conditions of safety". Now, the approach is to say other trains are allowed if you can make a convincing case that they can be evacuated safely in the event of a fire. So far no-one has, and it's hard to see how they could unless the safety philosophy changes.
