SINGAPORE - Works are afoot to replace the corrugated roof sheets of terraced houses in Chip Bee Gardens after asbestos was found in some of them.
Residents in the private housing estate beside Holland Village have voiced safety concerns, citing the harmful nature of asbestos.
The fibrous mineral, once a popular component in construction materials, is linked to health problems such as lung cancer. Its use in buildings was banned here in 1989, but many earlier structures still contain the substance.
While the 349 state-owned black and white terraced houses in Chip Bee Gardens were built in the 1960s, the use of asbestos there was uncovered only in April this year.
The Singapore Land Authority (SLA), custodian of state-owned properties, said this happened on April 26, when a contractor inspecting a broken roof above the front porch of a vacant house in Jalan Puteh Jerneh noticed that the material could contain asbestos.
Tenants in the area were notified the next day via a letter from EM Services - the estate's managing agent.
Why asbestos is harmful
Asbestos is a group of naturally occurring minerals which have, among other traits, good thermal resistance, chemical stability and high tensile strength.
These qualities made it widely used in building and construction before it was banned in many countries from the 1980s due to its harmful effects on health.
Exposure to asbestos can cause serious lung diseases, including asbestosis (the thickening and scarring of lung tissue), lung cancer and mesothelioma (cancer of the chest and abdominal lining). Symptoms may take decades to manifest.
Explaining the carcinogenic nature of asbestos, Professor Philip Eng, a senior consultant respiratory physician at Mount Elizabeth Hospital, said: "The asbestos fibre is very light and can penetrate deep into the lungs. This can irritate the cells and cause them to mutate."
But doctors told The Straits Times that exposure to asbestos dust must be prolonged and in significant amounts for any harm to kick in.
"You need at least 10 to 20 years of continuous exposure to get asbestosis," said Associate Professor Suresh Pillai, senior consultant at the National University Hospital's emergency medicine department.
In Singapore, the Ministry of Manpower oversees asbestos removal, while the National Environment Agency regulates its disposal .
Asbestos specialist and managing director of Stallion Engineering Contractor Andy Jiang, 32, said many buildings here built before 1991, including schools, landed properties and army camps, may contain asbestos.
It is often found in ceiling boards and corrugated roof sheets. He said: "As long as the material is in good condition, there won't be any problems. But if there are cracks or holes, I would advise removing them."
It is safe to stay home while asbestos removal is done next door by an approved asbestos removal contractor as the work area has to be covered up under regulations, Mr Jiang said.
But he added: "I would advise neighbours to shut their windows just as a precaution."
Yeo Sam Jo
The damaged porch roof was removed on April 29 and replaced on May 3. Lab testing revealed that the original roof contained chrysotile, a common type of asbestos.
Tests done on two other terraced houses in the neighbourhood also uncovered asbestos in their front roof sheets, the SLA said. This has unsettled some residents, who fear that their roof sheets, or awnings, might be unsafe.
Sixteen of them organised a meeting with the SLA on May 17 to discuss the matter.
Housewife Essa Tay, 34, who lives directly across the house with the broken porch roof, said: "I feel uncomfortable. I'm especially worried because I have a two-year-old daughter and I'm pregnant."
Housewife Marisa Howie, 39, who lives on the same street with her husband and two children, said she is also concerned.
Pointing to her awning, the Australian said: "Mine is not in good condition. Some bits have come out."
Citing the Ministry of Manpower (MOM), which regulates asbestos removal here, the SLA said roof awnings with asbestos are not easily crumbled, and unlikely to become airborne or pose any health risk to occupants if they are intact and not disturbed.
Disturbance entails sawing, cutting or replacing the material, which may cause asbestos fibres to become airborne.
As an interim measure, an asbestos specialist hired by the SLA will visually inspect 323 terraced houses with corrugated roof sheets over the next few weeks, and check for cracks and damages.
The remaining 26 units are not affected as they have clay-tiled porch roofs that do not contain asbestos.
So far, SLA's specialist has inspected the roof awnings of 110 houses in the estate.
About a tenth of these were found to be in good condition, while 20 per cent of them are substantially damaged and require removal. The remaining 70 per cent have some cracks and damages and will be coated with a sealant.
Depending on their condition, the roof sheets will either be left alone, coated with sealant or replaced.
"Should repairs or replacements be needed, they will be carried out promptly and safely by our asbestos specialists and in accordance with MOM guidelines," said the SLA.
Under these guidelines, asbestos removal has to be carried out by an approved asbestos removal contractor and MOM has to be notified. A plan of work needs to be established to ensure the removal is done safely.
The work area must also be enclosed to prevent the spread of asbestos.
As tenants have to move out during the replacement of awnings, which takes about two to three days per unit, the SLA said rent will be waived for that period.
When The Straits Times visited Chip Bee Gardens last week, three houses along Jalan Hitam Manis were enclosed in sheets for asbestos removal.
Director of SLA's Land Operations (Private) Division Lee Seng Lai said that as a precaution, SLA plans to progressively replace all affected roof awnings in the estate within the next 18 months through a tendered project.
"We have explained the situation to the tenants and will continue to keep them informed of the progress with the on-going works."
Mr Lee added that asbestos removal is "not unusual" for old state properties, citing examples such as Hume Heights estate, where asbestos was removed from some vacant houses in 2012. There were more than 250 cases of asbestos removal in Singapore last year, and an average of about 200 cases each year, according to MOM figures.
Some Chip Bee residents want their roofs to be replaced sooner, however.
Others want better compensation for having to vacate during the asbestos removal, while some felt they were not receiving enough updates from the SLA. These residents questioned if it is safe to stay home when their neighbours' awnings are being replaced.
Still, there are tenants who are less troubled, with some even preferring that the awnings be left alone.
Said a 40-year-old Jalan Hitam Manis resident from New York: "I was born in the 1970s when asbestos was alive and kicking. I don't think of it as a problem.
"I'll be worried when they start ripping the roofs out and replacing them. That's when it's dangerous."
The SLA consulted with MOM, and said residents may remain in their houses while asbestos removal is underway next door, as measures will be in place to prevent the spread of asbestos.
But Chip Bee resident and hedge fund director Ian Seow, 37, said: "Going by the book is one thing, but this is an issue of health. We don't want to take any chances."