We know, we were a bit confused at first too. The Citaro in question was in fact converted to large-scale treatment and transport vehicle; during the record setting attempt, the bus managed to accommodate 123 people.
Daimler's record challenge took place in front of the Rhineland-Palatinate Federal State Parliament building in Mainz. Three vehicles took part in the presentation: the aforementioned treatment and transport Citaro (bus variant B), a Citaro converted in a mobile intensive-care unit (bus variant A) and a third, which is a combination between the two (bus variant C).
The three buses were ordered by Dubai, to be used in the event of large scale accidents, incidents or disasters. They were converted by Gebruder Heymann, based on the designs made by consultancy agency Von Bergh Global Medical Consulting.
"The entry in the Guinness Book of Records is the latest chapter in the MercedesBenz Citaro success story. On 8 September, Citaro bus number 25,000 was handed over to a company called infra furth verkehr gmbh, making the Citaro the most successful urban bus of all time," Daimler said in a proud, proud statement.