This should help allay public concerns over the project’s safety, she added.

But the commission described the issues as “isolated and sporadic incidents”.

“The commission is satisfied that this was not a widespread nor systematic failure,” it said, and added that there was no need to rebuild the structures in question.

It said that based on all the evidence, including that of five independent structural engineering experts, the panel were confident the work was safe and no rebuilding was necessary.

However, questions remained on Tuesday about the safety of the project because the commission’s report came before the conclusion of tests by the city’s rail operator on steel bars used for the new platforms.

After reading the report, Lam said, the Department of Justice had advised against publishing it in full, to avoid prejudicing ongoing criminal investigations.

Lam said the full unredacted version would only be made public after legal proceedings had ended.

Substandard work on Sha Tin-Central link may have affected a second platform at Hung Hom station

Since October the commission has been investigating construction scandals that have enveloped the line, the city’s most expensive rail project ever. Hartmann is a former non-permanent judge on the city’s top court. The panel were tasked with investigating claims of poor work on the new platforms.

During the inquiry it was confirmed that some steel bars had been cut short during installation when they could not be screwed into couplers on a platform – a scandal that engulfed contractors, the MTR Corporation and the government.

Leighton was also embroiled in allegations that the designs for supporting diaphragm walls were changed without authorisation.

Critics were not satisfied with the panel’s conclusion that the project was safe although pro-government lawmakers accepted its ruling.

Civic Party lawmaker Tanya Chan questioned if the panel had made a premature evaluation, as tests on the steel bars were still continuing.

Since December last year, the MTR Corp has been testing with ultrasound tools how deep steel bars had been screwed into couplers on the platform.

After the initial method was proved inaccurate, the railway firm improved its methods and restarted the tests last week.

“They have only tested 48 out of 240 [steel bars],” Chan said, noting that 27 per cent of them had failed to meet the required depth of 40mm.

Citing the same test results, veteran structural engineer Ngai Hok-yan said the panel’s report was “detached from reality”.

The engineer said the commission’s conclusion of shoddy works being “isolated” incidents contradicted the test results, and its assertion of safety was not convincing.

Ngai disagreed with the panel’s findings that the improperly installed steel bars would have no impact on the project’s safety.

The episode has already cost several top managers at the MTR Corp their jobs, with four – Philco Wong Nai-keung, Lee Tsz-man, Jason Wong Chi-ching, and Aidan Rooney – resigning in August.

Lincoln Leong Kwok-kuen, the CEO, and chairman Frederick Ma Si-hang, are also leaving their posts earlier than expected.

The commission was supposed to submit its findings by January 9, but after the panel asked for more time, the Executive Council, Lam’s top group of policy advisers, allowed it to submit the report by February 26. The commission finally handed its conclusions to Lam on February 25.

The panel noted there were instances when the threaded ends of steel bars were cut short, although these cases were not extensive. It said those responsible for the errors were employees of Fang Sheung Construction, a Leighton subcontractor. Fang Sheung could not be reached for comment on Tuesday night.

The expansion work at Hung Hom station started in 2013. It involves two sections – one linking Tuen Mun and Ma On Shan, the other Hung Hom and Admiralty. It was hoped the Tuen Mun-Ma On Shan section would open next year, but that has been delayed. The commission will submit its final report of the inquiry by the end of August.

Starry Lee Wai-king, chairwoman of the Democratic Alliance for the Betterment and Progress of Hong Kong, the city’s largest pro-government party, said although the report concluded the project was safe, the government should not halt ongoing tests by the MTR Corp on the structures.

She urged the government to disclose what action it would take against the rail operator and Leighton for failing to build the project as planned.

Another pro-government legislator, Michael Tien Puk-sun, questioned whether public resources had been wasted on a project design that wasn’t followed.

“If they didn’t need so many steel bars … then why was it designed that way?” Tien said.

Jason Poon, managing director of subcontractor China Technology Corporation and the whistle-blower on the shortened steel bars scandal, said in a statement that he was disappointed by the report.

He said a different assessment submitted by University of Hong Kong expert Francis Au Tat-kwong “clearly identifies a few areas which are structurally unstable”.

That report, which Poon said had been finished after the commission’s, was not yet available to the public.

But the commission argued Poon had not put forward any statistical basis for his projection that about 5 per cent of the steel bars had been cut.

“It appears to have been an arbitrary estimate,” its report said.

The MTR Corp welcomed the commission’s conclusions, but outgoing CEO Leong did say the firm’s project management system would be improved. The rail operator also reiterated that it reserved the right to take action against Leighton.

Leighton declined to comment on the commission’s report.