I've had an interest in this going back to the testing of the daft tramline paving used to define the side of a path which is for pedestrian or cycle traffic. They got this completely wrong with the ridges parallel to bike wheels and transverse on the foot traffic side. Many installations use the wrong profile, and those with steep and square edges and excessive height have brought down cyclists. There were extensive tests done by TRL for DETR that established the 'safe' height and profile some 20-25 years ago, but so far my attempts to find any documentation have not been successful. Similar research determined the profile for the rumble markings where the thermoplastic lining material (as dangerous as tar banding in the wet, especially if the friction factor is not enhanced) has little ridges moulded in. This was tested to determine the profile which would be sufficient to wake up a driver but not so bad as to pull down a motorcyclist.
The paving should not be used on corners, where it is more likely to be struck obliquely by the wheels (imagine the way the wheels can go sideways as you cross a badly installed dropped kerb) and drainage is important (ice can form when fillets of trapped water freeze).
Such features are also part of road repairs (small settlements in trench backfilling leave a ridge that kicks tyres sideways) and are IMO far more relevant than 'slippery' rails when crossing rail lines. The misalignment critical range is I reckon, between 5mm and 20mm. Less that this and you'll not notice in normal conditions. more and it becomes something you can see and have to positively 'lift' the bike to clear it. Yet railway crossings especially do not have a 'vertical' standard to emphasise to those carrying out inspections.
We did press to get tramway rail-road profiles (on the newly installed track) altered to +0mm to -6mm so that a tyre contact patch is more likely to bridge a rail to contact the 'road' on either side but that is about all, and a report on the notorious Walton Street Crossing in Hull before it was re-constructed showed massive vertical misalignments between rails and road panels. Interestingly you should actually make a RIDDOR report (HSAW - Section 3 being duty of care and reporting incidents affecting non-employees on the relevant sites) if you fall and injure yourself on a rail level crossing, and it should be entered in the signallers log, as for a very brief moment you might be blocking the rail line and at risk. Indications suggest that there is substantial under reporting of such events, and I'm looking for examples.
Failure to take the slippery state of one crossing with the appropriate level of urgency, highlighted in official reports for 12 years, eventually saw a pedestrian killed after she slipped and was unable to get clear of an oncoming train. Reporting faults keeps pressing the operators to keep standards high, and reduce risks. It may also drive the improvement of some detail - looking at some tramlines after even a short time in use, the edges abutting tarmac or concrete 'road' are positively enhancing the risk of trapping or kicking wheels of bikes, wheelchairs etc, and should drive the use of better designs, and higher maintenance standards at critical locations.
As an example of non reporting and poor maintenance standards*, one incident particularly fired me up. A couple on a tandem fell on a crossing and were helped up and clear of the 90mph main line by another cyclist, who had also fallen at the same location, as had his son, and others known to them, and a motorcyclist. The crossing is one of 4 on the same minor road which crosses the same rail line 4 times in under 2 miles, along with a staff access crossing to a relay room. Between 2 & 3 of the road crossings AND the staff crossing could be eliminated if the old station site, and a combination of some railway and some private land was used to put a new road on one side of the railway and links for the road loops on the opposite side connected. Improving things for all users
Thus I'm interested in comparing reports and A&E visits arising from falls crossing rails, with the logged incidents recorded by the rail operators (remember that there are around 400 railway operators in the UK - Network Rail is simply the largest of them).
*Photos taken by the couple on a visit after their crash show various defects, including a statutory sign lying face-up at the foot of the pole it should be fixed to, and 2 telephones to choose from (a redundant unit not removed?) to call a signaller in an emergency. Note here that in an emergency, stopping the trains as quickly as possible makes the recovery of people and large objects a safer task, it ranks in priority with the recovery of people from the line.