Underground rumbling from passing trains might disturb patrons trying to appreciate the arts at the West Kowloon Cultural District.
Noise from two railway lines running under the arts hub will exceed the specified maximum level for three key venues, an environmental impact assessment for the project shows - and an art critic says vibration could be a bigger worry.
But the arts hub says the problem will be offset by the design of the buildings.
According to the assessment, the maximum noise from the West Rail line in the Xiqu Centre for traditional opera will be 32 decibels, against a specified level of 25.
The Tung Chung Line will cause up to 56 decibels of noise at the M+ Museum and Lyric Theatre, against specified maximums of 35 and 25 decibels respectively.
The assessment report, which was open for public comment until August 21, has yet to be tabled to the Advisory Council on the Environment for endorsement.
Engineer Greg Wong Chak-yan, who is familiar with rail work, said 56 dB could be compared to the noise at construction sites without pile-driving, while 32 dB "should be very quiet".
All three venues meet the requirements for continuous noise level, but not the maximum level. Wong said the maximum level meant occasional noise that would not last long.
"It's not a serious problem, but of course the tough standards were made to suit an arts venue," he said.
The West Kowloon Cultural District Authority said ground-borne noise-control measures were incorporated into the design and construction of the cultural facilities built above the railways.
"Given the … railways' proximity to the arts hub, at-receiver noise and vibration control measures such as building isolation or box-in-box installations will be required in the design of relevant arts and cultural venues," a spokesman said, adding that there will be "no extra cost to the project".
He said the arts hub did not have an estimate of the noise and vibration levels after control measures were installed but it would strive to meet international standards.
"Building isolation can reduce up to 20dB of structural-borne noise, [and] typical box-in-box installation can reduce up to 15dB," the spokesman said.
Art critic John Batten said noise and vibrations could affect art appreciation.
"Will it affect the exhibition you want to put on?" he asked. "There's a worry there and there will be more concerns about the vibrations.
"Most museums have concerns about vibrations. Is that the right spot for M+?"
Wong said the problem could be alleviated by improving the MTR tracks or laying noise-absorbing material in the venues.
"But either way, it shouldn't cost much, and the costs should be shouldered by the district authority," he said. "The railways have always been there, and it was the authority which chose to build on top of them."
The MTR said it would contact the authority for more information.