Network Rail needs to do a "massive amount" to make level crossings safer, the parent of a teenager killed by a train has told MPs.
Tina Hughes, who now works with the firm on improving crossings, said Network Rail had made changes but were only "scratching the surface" of what needed to be done.
Ms Hughes's daughter Olivia Bazlinton, 14, and her friend Charlotte Thompson, 13, were hit by a train in 2005 as they crossed the tracks at Elsenham in Essex.
Ms Hughes, who works with Network Rail as its "level crossing user champion", told MPs: "I believe that they have made very significant changes but they are only just scratching the surface of the things that they need to do. There is a massive amount of work that needs to be done."
Olivia's father Chris Bazlinton, appearing alongside Ms Hughes in front of MPs on the Transport Select Committee, said he believed information about their deaths had been covered up in a "conspiracy of silence".
Families from this region whose children were killed and seriously injured at railway level crossings have been at a parliamentary inquiry which opened in London today.
The parents of Olivia Bazlinton, who died alongside friend Charlotte Thompson at Elsenham near Bishop's Stortford, were among those to appear before the Transport Select Committee.
It is claimed that Network Rail put financial considerations above public safety.
Matthew Hudson reports.
The father of a teenager who was killed at a level crossing in Essex has accused Network Rail of a cover-up - as he prepares to speak at a parliamentary inquiry later today.
Chris Bazlinton's daughter Olivia died with her friend Charlotte Thompson in Elsenham eight years ago.
Today he will join the grandfather of a boy who was badly injured at a crossing in Beccles, Suffolk, in front of the Transport Select Committee this afternoon. The inquiry will look at safety at level crossings.
Today Mr Bazlinton said he wanted to know why key documents linked to the investigation into his daughter's death were not made public sooner.
Network Rail says it has promised the families it is committed to making the railways as safe as possible.
The parents of two teenage girls killed at a level crossing on the Essex/Hertfordshire border are to give evidence at a government inquiry today.
Charlotte Thompson and Olivia Bazlington died after being hit by a train at Elsenham in December 2005.
The Transport Select Committee is looking into Network Rail's safety record.
The mother of a 14-year-old girl killed on a level crossing in Essex, has welcomed the news there is to be an inquiry into the safety of all level crossings in the UK. Olivia Baslington and her friend, Charlotte Thompson, were hit by a train at Elsenham Station in December 2005.
Tina Hughes says she hopes the Transport Select Committee inquiry, which is likely to be held later this year, will keep the spotlight on level crossings.
Network Rail executives will appear in court in Chelmsford today to be sentenced over the deaths of two teenagers at level crossing in Essex.
Olivia Bazlinton and Charlotte Thompson were killed by a train in 2005 at Elsenham station near Stansted.
Network Rail pleaded guilty to Health and Safety breaches at an earlier hearing