ProMods

Research on object/obstruction markers in tunnels for various countries

• Iceland
  
  Black/white
  Traffic signs Iceland (unofficial)
• Norway
  
  Black/white
  Wiki, road tunnels in Norway
  
  
  
  
  
  Example of signage
  
  
• Sweden
  
  Blue/yellow
  
  

I'm not familiar with a lot of tunnels but AFAIK

• UK

NONE
A27 Southwick Tunnel
A3 Hindhead Tunnel
A282 Dartford Crossing Tunnel
A102 Blackwall Tunnel

In the Netherlands:

Also NONE, (apart from the emergency signs):

N11, Vliettunnel
A4, Schipholtunnel
A10, Coentunnel
N62, Westerscheldetunnel

We do have these kind of signs before most (longer) tunnels:
Tunnelname + Ontsteek uw lichten
Tunnel sign + length of the tunnel
waterway name + length of the tunnel

• Finland

Finland doesn't seem to have any markers inside the tunnels themselves either (Source: I drive through Markkinamäki tunnel on a daily basis). We do have signs before and after tunnels though.

This is the tunnel I was referring to above. The tunnel sign can be seen on the right (the blue sign with a black image representing a tunnel on it). The "extra" bits on that sign are the name and length of the tunnel.
Here are example signs from Wikipedia:

No obstruction markers in Estonia. Example of tunnel signage (only example )

In Latvia, we DON'T have ANY tunnels!

In Lithuania we DON'T have long tunnels, only this one (as I know) - https://www.google.co.uk/maps/@54.69368 ... 6656?hl=en

In Greece we have these road markings in white and red but in some tunnels only and we use it also for tunnels which the traffic flow happens only from one direction.In other tunnels we have these small red and white lights for the fog-night (last picture).Here the road system is a little bit complicated! (I leave the links for the signs and for the tunnels below.) {NOTE: The signs in the link are in Greek language}

The signage in Greece [There are even more but i can't find them at the moment.]:
http://users.sch.gr/garantz/drupal/?q=node/346

The Tunnels:
http://www.thestival.gr/media/k2/items/ ... 114_XL.jpg
http://i.ytimg.com/vi/MWpaOk14rWw/maxresdefault.jpg
http://www.skaikairos.gr/system/weather ... %20028.JPG
http://i731.photobucket.com/albums/ww32 ... ine2-3.png
http://www.patrasevents.gr/imgsrv/f/full/937473.jpg
http://www.pamepreveza.gr/Portals/0/Pam ... tounel.jpg

No markers in the NL, but we like safety, so newer tunnels have barriers so pedestrians are safe (no pedestrians allowed of course, but in case of emergency), and we're using cat-eye reflectors too. And emergency lanes too. Safety rules for new tunnels are strict. Example;

A2, Leidsche Rijntunnel, Utrecht

That really is the only tunnel which has that.. Even the new A2 tunnel in Maastricht doesn't get that stuff..

I believe that 'Emergency lane' is only there for the availability of an extra lane, which may be needed in the future.