Croatian news media report that this section of the track was reconstructed in 2005 and that the particular train passed inspection just two days prior to the accident, but the accident brought back the debate on whether these trains are appropriate for local conditions. Investigation continues, with questionable application of fire retardant (recently changed to „aqueous based resin liquid penetrate“ TG-300[6] from a new supplier) emerging as the most likely cause of this accident.
Croatia|label=Site of the derailment|position=left|lat=43.554 |long=16.3655 6 people have died and 55 have been injured after a train derailment in Croatia. The accident occurred on July 24, 2009 at 10:08 GMT near the village of Rudine, on the Zagreb-Split railway line.<ref> url=http://newsok.com/train-derails-in-southern-croatia-many-injured/article/feed/61031?custom_click=rss| title=Officials: 6 dead in Croatia train crash| work=NewsOK| author=Budmir, Milena| date=July 24, 2009| accessdate=July 26, 2009| </ref><ref>[http://maps.google.com/maps?t=h&ll=43.570115,16.311307&z=17 Derailment site (estimated)]</ref> Croatian media say that this is the worst railway accident to have occurred in independent Croatia to date, adding that if the train had derailed into a ravine 30m ahead, the death toll could have been much higher.
The accident happened when the two-carriage tilting train derailed at 10:08 GMT (12:08 local time) near the village of Rudine, around 30km (19 miles) from its destination. The front carriage hit the sides of a cut through a hillside twice, before breaking apart from the second impact. According to Croatian news reports, the cause of the derailment was slippery fire retardant that was just sprayed on a steep downhill section of the track, a normal practice in extreme summer heat but executed improperly<ref>title=Drago Rogulj mobitelom snimio polijevanje tračnica|url=http://www.jutarnji.hr/vijesti/clanak/art-2009,7,30,,171299.jl|work=|archiveurl=http://www.webcitation.org/5ixpOY0jc|archivedate=2009-08-12|deadurl=no|accessdate=2009-08-01</ref> using a new chemical. With brakes ineffective, the train gained a speed higher than the track configuration could handle and derailed.<ref>[http://www.hrt.hr/index.php?id=48&tx_ttnews%5Btt_news%5D=44080 Jeziva željeznička nesreća]</ref><ref>[http://www.hrt.hr/index.php?id=48&tx_ttnews%5Btt_news%5D=44169 Kriv je premaz pruge - slijede prijave]</ref><ref>[http://www.vecernji.hr/vijesti/vlak-smrti-glavni-predmet-istrage-ivan-medak-drago-rogulja-clanak-5666 Vlak smrti: Glavni predmet istrage Ivan Medak i Drago Rogulja]</ref>
Shortly after the crash, a railway service vehicle coming to the site of the accident to help, also lost braking and at excessive speed nearly hit emergency workers and reporters, who quickly scrambled off the track. No one was injured in the incident, which was filmed by a TV crew. <ref>title=VIDEO: Lokomotiva skoro ubila spasioce|url=http://www.rtl.hr/index.php?cmd=show_clanak&clanak_id=9771|work=|archiveurl=http://www.webcitation.org/5ixpFhZuY|archivedate=2009-08-12|deadurl=no|accessdate=2009-08-01</ref>
Croatian news media report that this section of the track was reconstructed in 2005 and that the particular train passed inspection just two days prior to the accident, but the accident brought back the debate on whether these trains are appropriate for local conditions. Investigation concluded that fire retardant not suitable for railway use (water-based TG-300 from an American supplier), together with questionable method of application is most likely the only cause of this accident.
From the very beginning of the rescue operation, the initial investigation was focused on the fire retardant that was sprayed on the railroad approximately 10 minutes before the train has derailed. Investigators were suspicious about traction on the tracks because the rescue train, which was ironically the same railway service vehicle that supported spraying of the fire retardant, suffered a loss of braking and derailed at the same location as the passenger train.
On July 27, 2009, a cleaning operation on the 11 km stretch of railroad between the stations Kaštel Stari and Labin Dalmatinski begun, but was stopped within an hour because of a new discovery important for the investigation. The cleaning teams followed the fire retardant supplier's directions and washed the tracks with hot water. However, the cleaning supervisor quickly noticed that while most of the retardant washed off, a yellow-brown film of an unknown slippery substance remained on the tracks. A sample of the substance was taken as evidence and sent to Zagreb for chemical analysis. According to the TG-300 retardant description<ref>title=TG-300 Outdoor Applications|author=DCtop <!-- BOT GENERATED AUTHOR -->|url=http://www.firechemicals.com/TG300TechInfo.pdf|work=|archiveurl=http://www.webcitation.org/5ixpMOv9K|archivedate=2009-08-12|deadurl=no|accessdate=2009-08-01</ref>, it is an „aqueous based resin liquid penetrate“ but its exact composition is unpublished.<ref>title=Za tragediju na pruzi kriva je nepoznata smola?|url=http://jutarnji.hr/vijesti/clanak/art-2009,7,27,,170942.jl|work=|archiveurl=http://www.webcitation.org/5ixpMk0Yr|archivedate=2009-08-12|deadurl=no|accessdate=2009-08-01</ref> Three days after this accident, the fire retardant manufacturer added a warning „do not spray on tracks“ to their TG-300 web site.<ref>[http://www.firechemicals.com/ TG-300 web site]</ref>
Police brought to the interview responsible people from the HŽ supply office as well as the responsible people from the company that had imported retardant. Director of HŽ Infrastructure, a company within HŽ Holding, and two of his associates were removed from their positions by the act of Traffic minister Božidar Kalmeta<ref>title=Title Unknown <!-- BOT GENERATED TITLE -->|url=http://www.hznet.hr/iSite3/fgs.axd?id=3150|work=|archiveurl=http://www.webcitation.org/5j3DHooEU|archivedate=2009-08-15|deadurl=no|accessdate=2009-08-13</ref>. Two people who played the most important role with purchase and application of the retardant were, by the order of new HŽ Infrastructure director, put on suspension and subsequently fired from the company.<ref>http://www.hznet.hr/iSite3/fgs.axd?id=3148</ref>.
After recovering the wreckage from the site and needed track repair, the traffic was resumed on August 2, 2009 at 20:00 GMT for freight traffic only, while the scheduled passenger service resumed the day after on August 3, 2009 at 4:00 GMT.
Tilting train derails in Croatia, six dead *[http://www.rtl.hr/index.php?cmd=show_clanak&clanak_id=9771 Video of the railway works vehicle narrow miss] *[http://www.jutarnji.hr/galerija?galleryId=526 Photo gallery]