Dublin Bus will today begin its official inquiry into last Saturday's fatal accident at Wellington Quay in which five people died.
The first phase of the investigation will be in private, but a further public inquiry has not been ruled out.
A spokeswoman said last night the six-week inquiry would be very concentrated and intense and this was partly why four international experts had been engaged to move things along.
The investigation team last night finished interviewing the two bus-drivers involved in the fatal crash.
The company was given medical sanction to begin questioning the drivers on Wednesday.
Their statements and accounts will be fed into the inquiry, the Dublin Bus spokeswoman said.
The terms of reference of the inquiry, which Dublin Bus stresses is completely separate from the Garda investigation, are to investigate the circumstances of the accident and to establish the cause and any contributory factors of the crash.
The structure of the investigation was currently "quite loose", the spokeswoman said.
"The committee will initially need to meet to decide the topics and modules, but there will be technical and human components and will involve the reports of eyewitnesses."
A number of working groups will support the main committee, providing such information as technical studies and "peer review" reports.
Mr Arnold O'Byrne, a Dublin Bus board member, will act as chairman of the inquiry.
Mr O'Byrne is the current chairman of the Dublin Bus audit review group. He was previously chairman and managing director of Opel Ireland.
The investigating committee will be made up of eight other members including three Dublin Bus officials and four international experts.
Dr Alan Westwell, managing director of Dublin Bus, joined the company in 1997 and has more than 40 years experience in the public transport industry.
He has been chief executive of a number of large public transport organisations in major UK conurbations.
Mr Shane Doyle, chief engineer with the company, joined CIÉ in 1977 and became chief engineer in Dublin Bus when the company was established in 1987.
Mr Mick Matthews, the operations manager of Dublin Bus, has worked with the company as a conductor, driver, inspector, scheduler, industrial relations executive, divisional manager and area manager.
The final Dublin Bus official on the team is Mr Joe Hogan, the company's risk manager.
He joined CIÉ in 1971 as a mechanic and was promoted through the ranks of supervisor and engineering manager. Mr Hogan was appointed risk manager in 1999.
The international experts include Mr Wolfgang Arnold, engineering and infrastructure director with the Stuttgart Transport Authority, Germany; Mr Hugo van Wesemael, former director general of Lijn Transport, Flanders, Belgium; Dr Richard Lambourn, lead investigator with the UK Transport Research Laboratory; and Mr Simon J. Brown, former group engineer with London Buses Ltd.
