The coating material of cable trunking used in a redevelopment project at Kwong Wah Hospital was not up to standard in both its thickness and weight, according to an expert report.

The Hospital Authority (HA) earlier appointed an independent expert to conduct tests following media reports that corners might have been cut involving the coating material of cable trunking used to protect electrical wires at the hospital.

"The test data showed that the thickness of the cable trunking coating material is less than the standard of 20 [micrometres], amid the weight does not meet the relevant standard of 275 gram per square metre," said Andrew Wong, a chief manager at the authority.

"The independent expert confirmed that the thickness and weight of the cable trunking coating are substandard and do not meet the standards stipulated in the project contract."

The HA said on Thursday that it has taken follow-up action against the contractor, and requested a detailed investigation and explanation.

The project consultant and contractor have also been told to reinstall the substandard cable trunking without affecting the hospital's operation, and bear the additional expenses and losses incurred by the HA.

The Architectural Services Department, for its part, said it’s very concerned about the incident and is arranging testing for cable trunking samples from 148 ongoing works contracts to ensure their coating comply with contract requirements.

"If any non-compliance with the required coating thickness under the contract is found after testing, we will require the contractor of the relevant works contract to give explanations and make appropriate arrangements in accordance with contract terms," a department spokesperson said.