From the Sunday Express

It really is not that simple. 

In the short term some things might save costs, but ultimately (when all the bugs are ironed out), for example standardising signalling kit will save money. At that time it will not be cost effective to buy anything other than ERTMS^▸ (European Rail Traffic Management System.) equipment because it will be the standard kit in so many countries and anything else would be a one off so expensive.   

We are in Europe - geographically and our manufacturers (if we still have any) will be manufacturing for that market and our other main suppliers are European so in practice we will continue to be bound by many of the EU^» (European Union - about) standards whether we like it or not. 

In other sectors we learn that ultimately when a European Standard has been developed other manufacturers also want it adopted as an international standard to make it easier for them to export to both European and non- European countries alike. 

...eh?  There are currently over 6000 Railway Group and NR^» (Network Rail - home page) standards that cover the UK^▸ (United Kingdom) network.  They are mostly quite prescriptive 

New trains not allowed leather seats??? Not heard that one. Reasons given for this rule?

Quite agree, if anything they are more onerous than the BR^▸ (British Rail(ways)) "standards"



Basically yes, the DfT^» (Department for Transport - about) insisted that NR complied with TSI's, yet the EU interoperability directive allows each administration to waver requirements, however UK HMG have been hard task masters in regards TSI.  In part why electrification between Chippenham and BTM^▸ (Bristol Temple Meads (strictly, it should be BRI)) started to be come expensive was the requirement for 3 metres electrical clearance and not the UK norm of 2.75 metres

The relevant standard for fire safety of seats was EN 45545-2: 2013, "Railway applications — Fire protection on railway vehicles" Part 2 being "Requirements for fire behaviour of materials and components". I found an RSSB^▸ (Rail Safety and Standards Board) report (T843, on Spark) about this standard dated January 2014, which says, about the materials standards:

However, it also had this observation about test methods for whole seats:

Now, those might not correspond with what you expected. My guess is that, when the group called to work on the standard assembled, there were no experts on those test methods present. This is always a risk with standards - participation is voluntary and generally unpaid, for individuals and/or their employers, and it can be hard to persuade the people you really need to bother. This standard was prepared by CEN under an EC mandate, presumably issued via the ERA. In this field there is an older body, the UIC, that is in a sense a rival of the ERA and feels threatened by it - which doesn't help.

RSSB, and no doubt others around Europe, proposed changes as part of an amendment planned for 2015 (the initial version had some known incomplete areas). An amendment did appear, so the standard is now EN 45545-2:2013 +A1:2015, though I've not yet found out whether it addressed this issue.