Shanghai Zhuoyou Building Decoration Engineering Co., Ltd

Is safety glass safe?

2015-08-23

In the explosion accident which occurred in Binhai New Area of Tianjin, many nearby residents were scratched by the instantaneous blasting of the glass. what’s worse, a lot of sharp pieces crashed into the cement wall. The reason that the so-called safety glass, when broken, did not turn into particles without sharp edges as expected, became the focus of public attention. A reporter from Beijing Youth Daily, who found in the survey that the glass used in domestic expensive housing is mostly priced between 150 yuan and 200 yuan per sqm, said that even many famous brand commercial properties didn’t meet the standard in terms of the safety performance of the glass.

In addition to the influence of the blast itself, a growing number of security problems arising around residential areas were exposed. It was reported that a lot of the wounded were scratched instantaneously at that time of explosion. Most of the glass in these residential buildings were shattered and the remained could also hurt people at any time like "sharp knives". Furthermore, there were even reports of shattered glass, by strong impact, crashing into the wall like a dagger, which would lead to inconceivable consequence if any resident got shot unfortunately. These images also raised some doubts from outside about whether safety glass was employed for the residence and whether it was in compliance with the security standards of architectural glass.

Focus

Does the Glass Used in Vanke's Properties Conform to the Safety Standards?

The residential buildings near the explosion site were developed by such brand companies as vanke, so it concerned the outside world all the more on whether the project quality was in line with requirements. On the windows of the three concerned projects, Vanke claimed that all the Windows, either their design and installation or the acceptance tests on them, were in compliance with national and local relevant rules such as "Tianjin Technical Specification for Application of Energy Saving Doors and Windows", "Technical Specification for Application of Architectural Glass", "Regulation on the Administration of Architectural Safety Glass” and the like. Complete and thorough reviews had gone through on their blueprints and working plans. The two construction companies involved, Liaoning Yuhong Doors and Windows Co., LTD and Shenyang Huaxin Doors and Windows Engineering Co., LTD., were all benchmarking enterprises. All materials, already enclosed with quality certificate and test report, were inspected once again before entering the construction site, in order to ensure its compliance to the requirements of the working plan. All of our delivered projects proved satisfactory and obtained the Certificate of Permission to Deliver and Use.

In that case, why did the "safety glass" change into many sharp knives rather than particles without pointed edges instead? Regarding this issue, Beijing Youth Daily interviewed Ding Xiaochang, director of China Building Glass and Industrial Glass Association Secretariat. He believed we could not conclude, if judging from site conditions alone, that it happened so just because the glass was unqualified. He said, the glass itself was a kind of brittle material, which explained the inevitable posibility of special circumstances under abnormal conditions. Such an extraordinary accident was too much to take for the glass with normal standard.

Regulation

The Current Regulation on Architectural Safety Glass was issued 11 years ago

Ding Xiaochang also believed, though, that the security problem of architectural glass was once again placed in front of the public. He represented that in fact, as early as 2004, a Regulation on Architectural Safety Glass had been jointly issued by the NDRC, the MOC, the AQSIQ and the SAIC, requiring to use safety glass in the entrance and hallway of public buildings where glass is used.

In accordance with the provisions of Article VI, safety glass is required in the following 11positions where glass is used as the building material, including the outward-opening windows on the 7th floor and above, glass windows with an area of over 1.5 sqm or french windows with a distance of less than 500mm from the bottom edge to the final decoration surface, tilted fabricated windows in curtain wall, all kinds of sunroofs and glass hung ceilings, floor slabs to bear walkers, the observation window or peephole of the aquarium and the swimming pool, entrance and hallway of public buildings, and other parts that will pose potential hazards to human bodies. It is true that such provisions have been out of date for modern cities with high rise buildings everywhere.

Beijing Youth Daily also learned that probably, the creators had in mind the economic development situation at the time when drafting the regulation 11 years ago, for the regulation did not cover county-level cities, only applicable to those municipal or superior probably. Free from restrictions, nearly all glass used for the doors of shopping malls and stores in county-level cities was ordinary glass, coupled with undemanding installation. As a result, it created some serious potential safety hazards as the occasional incidents of people hurt by glass door.

So some insiders put forward that, as modern architecture industry is continuously upgrading, buildings are becoming higher and higher, and all kinds of building styles are cropping up here and there, the specification has obviously lagged behind. There are professionals who even believe that the specification fails to ask for comprehensive use of safety glass and as such, it is already subject to a revision.
It is also learned that in 2009, the Ministry of Housing and Urban-rural Development made a revision to the industry standards of "Technical Specification for Application of architectural glass”, among which, though, there was only a request for the use of safety glass, but no mandatory regulation.

Interview

Glass Curtain Wall Is An "Untimed Bomb" Hanging Over the Head.

According to a reporter at Beijing Youth Daily, in addition to such malignant accidents as this deadly blast in Tianjin, those tall buildings in modern cities, packed by glass curtain wall, are very likely to become a "untimed bomb" over our heads if the glass is unqualified. It is known that the glass curtain wall now common in people’s sight first appeared in the 1950s in the United States. It has been 30 years since it was introduced into China. The first batch of glass curtain wall has already gone beyond its safe using time, but it is rarely to see in a building an overall replacement of its glass curtain wall.

According to the insiders, “Building Safety Glass” does not just refers to changing into particles with no pointed edges. Even if it happens so, in fact, when falling down for high rise buildings under the action of gravity acceleration, these particles will hurt or even kill people. Therefore, for architectural glass, especially in high-rises, it is not enough to only focus on its broken forms. What matters more is how to prevent unnecessary crushing under impact or in temperature changes.

Problems

Vicious Pricing Environment Affected Safety Glass

There are a variety of safety glass, including the tempered glass mentioned above which will turn into particles without sharp edges when broken, fireproof glass with low infusibility under high temperature in case of a fire risk and laminated glass with sticky material between layers so that the broken glass will not fall and injure people. Different types are suitable for different areas. The tempered glass is usually for high-rise buildings and the laminated glass for large hollow glass ceilings.

It is acknowledged in this industry that building safety glass technology keeps improveing. There is no strict supervision however, which acts as the key factor that leads to the current mixed situation of architectural glass. Li Chunchao, sales director of Beijing North Glass Safety Glass Co., LTD, said in an interview by Beijing Youth Daily that malignant price competition is the important cause of the chaotic in architectural glass market. “At present”, he said, “Either home owners or developers or decoration companies, when choosing glass, often focus first and foremost on the price rather than its performance indicators.

Besides the glass used for civilian residence, Li Chunchao particularly proposed the safety issue of the glass for large commercial facilities, "these facilities are often built in busy areas, adjacent to the street, where people frequently come and go downstairs. So it will be quite dangerous in case that something is wrong with the glass." Nevertheless, even many well-known brand commercial properties are not up to standard in terms of safety performances of the glass, since they give top priority to cost reducing and construction time shortening. They have created and are creating "untimed bombs" hanging over our heads.

It is learned that China has alreadly taken safety glass production into the scope of 3C and made strict qualification requirements on manufacturing enterprises. But industry sources say, "Since 3C is just a qualification certification for a production enterprise, so it is hard to say whether its later production is exactly compliance with the standard, whether there is strict supervision, and whether the products on the market are qualified or not.”

According to Li Chunchao, it is not true that China is not unable to produce quality glass. To illustrate this statement, he used his company, Beijing North Glass Safety Glass Co., LTD, as an example. He said, its products, 80% of which are all manufactured for export, are even selected for glass wall of Apple’s headquarters in the United States as well as Apple stores in Beijing. But he also admitted that the price of at least ten thousand Chinese yuan per sqm is too high for many domestic builders.

Beijing Youth Daily reports that it is easy to acquire cheap safety glass on the present market priced at no more than CHY 200 per sqm. The lowest price is even just a little above100. Its survey reveals that currently even for those medium and high-grade residence domestic, the prices of the glass used are around 150 yuan to 200 yuan per sqm.

Despite the visible big difference in price, yet for the intrinsic quality, only professionals can tell out the differences. They explained that, the performance of safety glass not only depend on raw materials, but also on the processing technology, which is exactly beyond the buyers’ knowledge.

news

Is safety glass safe?

2015-08-23