Fire tests on building cladding too lenient; certification process can be improved: Experts

Fire tests on building cladding too lenient; certification process can be improved: Experts

SINGAPORE: When Parliament sits on Monday (Sep 11), questions will be asked about how building cladding that was not fire-safe got past regulations and inspections, and whether more stringent tests are needed.

The issue arose after it emerged last month that cladding used on a building involved in a deadly fire at 30 Toh Guan Road did not meet safety standards. 

Construction firm Chip Soon Aluminium is under investigation for having supplied the cladding for the building, as well as similar cladding for scores of other buildings in Singapore.

Police investigations found that stocks of cladding panels with different fire safety ratings were mixed together at Chip Soon's warehouse, meaning that some of the buildings could be using external cladding with less stringent standards.

As the Singapore Civil Defence Force (SCDF) looks into a review of fire safety regulations and processes for certification, it has been gathering feedback from industry experts, who questioned if existing fire tests were too lenient, and suggested changes to the way in which the cladding panels are certified.

FIRE TESTS TOO LENIENT? 

Consultant engineer Lee Seong Wee urged authorities to review the way cladding or composite panels are being tested for use in Singapore, saying that the existing test was too lenient.

The panels are made up of three layers: A thin, core material - which is combustible - sandwiched by two layers of aluminium materials which are non-combustible.

The requirement in Singapore is that the cladding panel must undergo a flame test on the core material instead of on the entire panel itself - but this was too lenient, said Mr Lee.

"If you imagine that the organic material would be the one that’s weakest, as far as fire is concerned, then I say, that part is stringent. If you consider the test itself to determine whether the material is suitable for an external cladding, then I say it’s a very weak test," he said. 

"When you have a cladding, are you going to test it as close to what is the real situation, or are you going to use this method which is basically flame-spread and then interpret from that result?

"I would say definitely a full-scale test to be as representative of a real fire as possible because one thing we must understand is that in a real fire, you do not take the flame away.”

IMPROVING THE CERTIFICATION PROCESS

Currently, some products, like fire-rated flooring, are selected by testers at the production line. But for cladding materials, samples are sent to the testers instead.

“To get a certificate, you should have people from the testing laboratory like Tuv Sud to go to your factory to take your samples. That way, you would at least know that the product that's tested is from the manufacturer," said Arjen Flierman, architectural solutions director of 3A Composites Asia Pacific Alucobond, who has given his feedback to SCDF.

"And this is what I told Civil Defence. Every cladding job which is done in Singapore - maybe during the construction stage - some sample pieces should be taken from the site as a compulsory regulation to make sure that compliant materials are used on buildings," Mr Flierman said.

Mr Flierman acknowledged that the testing method would come at a price. Factoring in the travelling and accommodation expenses for the testing officials, it could cost as much as S$20,000, compared with S$4,000 if the samples were sent to the testers, he said.

Chip Soon, the firm at the centre of the investigation, too, suggested that the testing process could be standardised. 

"MPs could possibly look at establishing a committee to standardise the entire testing process so that it’s not just (a case) where panels can be supplied based on certification, but rather from live testing when goods are shipped into Singapore before fabrication and installation," Chip Soon sales and marketing manager Benny Phua told Channel NewsAsia.

The panels in question were tested by Exova in the UK in 2011, and the test result was recognised by Tuv Sud PSB, one of four accredited certification bodies in Singapore that approves cladding materials for use in the country.

Tuv Sud PSB has since suspended its certification for the panels.

The owners of the buildings Chip Soon supplied the affected panels to have up to late October to remove them. 

They include mega lifestyle hub Our Tampines Hub, which has started doing so, and Singapore Polytechnic, which said it plans to remove all affected panels by Oct 15, when students return to school after their term break.

At least one building owner - that of 1 Changi South Lane - voluntarily removed its panels without conducting any tests.

Source: CNA/ec

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