The Building and Construction Authority (BCA) has issued stop work orders to 13 construction sites where workers from Sungei Tengah Lodge who tested positive for Covid-19 had been working.
A spokesman for the BCA told The Straits Times last night: "A stop work order is issued to the builder to rectify any shortcomings in safe management measures on site or introduce new measures to curb the risk of Covid-19 transmission."
The 13 are part of 20 construction projects that were issued a safety time out notice on Sunday.
The notice allows for the disinfection of affected areas and a review of onsite safe management measures, which typically takes up to three days.
The 20 construction sites consist mainly of commercial and infrastructure projects, said the BCA spokesman.
Sungei Tengah Lodge, Singapore's largest foreign worker dormitory with 16,000 residents, was announced to be a new cluster last Saturday, after two new coronavirus cases were linked to the 55 previous ones there.
It was the first of two new dormitory clusters in the almost two weeks since all foreign worker dormitories were declared to be clear of Covid-19.
On Sunday, a dormitory in Kaki Bukit was also announced as a cluster when a fresh Covid-19 case was linked to four previously confirmed cases at Homestay Lodge.
On Aug 11, the Ministry of Manpower (MOM) declared all dormitories to be clear of Covid-19, save for 17 standalone blocks which had served as quarantine facilities. Around a week later on Aug 19, the ministry reported that the blocks used for quarantine were cleared of Covid-19 as well.
In a joint statement on Sunday night, the Ministry of Health, MOM and BCA said: "The new cases detected in the cleared dormitories demonstrate the importance of ongoing surveillance and testing under rostered routine testing, as well as the need to remain vigilant and adhere to safe management measures."
Workers staying in dormitories are required to be swabbed for Covid-19 every 14 days.
In the light of the resurgence of Covid-19 cases in previously cleared dormitories, health economist Phua Kai Hong asked about the efficacy of the testing procedure.
Dr Phua, who is adjunct senior research fellow with the Institute of Policy Studies at the Lee Kuan Yew School of Public Policy, said: "This reflects on the trade-offs between the risks of infection control versus the approval to work by foreign workers. We have to screen with greater accuracy and public safety first before declaring the workers as fit to work, with different levels of certainty."
Maybank Kim Eng senior economist Chua Hak Bin noted that the recovery of the construction sector will be "sluggish and choppy".
"Projects may see starts and stops, as one Covid-19 case could trigger a quarantine for the whole dorm. Prioritising public health is important but will inevitably sacrifice some labour productivity and growth," he said.