Organic insulation materials, energy-saving or fireproof?

On May 25, a fire accident occurred in Kanglan Old Age Apartment in Lushan County, Pingdingshan City, Henan Province, causing 38 deaths and six injuries. The accident revealed that the production and business units violated the flammable combustible materials as the core material and their low-grade fire-resistant grades were used in color steel plate construction. On May 28, the office of the State Council's safety committee issued an accident report, requesting to focus on the use of polystyrene and polyurethane foam as a special rectification for decoration and insulation materials in public gathering places. Those who have not accepted fire inspections and violate the use of flammable combustible materials as color steel plates to construct buildings and use polystyrene or polyurethane foam in violation of their wall insulation shall be suspended from rectification.

This is another construction fire accident related to the illegal use of organic insulation materials. For polyurethane, polystyrene-based organic insulation materials industry, the accident once again touched the nerves of the industry. On the one hand, building energy efficiency is the trend of the times, and the market demand for organic insulation materials continues to grow. On the other hand, the fire safety situation is getting increasingly severe. How to harmonize the contradiction between building energy conservation and fire safety has become an urgent issue to be solved in the government management department, construction industry and insulation material industry.

Organic materials are indispensable

Li Jiapeng, a member of the China Petroleum and Chemical Industry Federation Flame Retardant Professional Committee, said that in the field of building insulation, organic materials such as polystyrene and polyurethane foam have incomparable advantages over inorganic materials, including high insulation properties and ease of construction. These organic materials are widely used in building insulation in the world. They are the first choice of exterior wall thermal insulation materials, and their market share in Europe and the United States exceeds 80%.

In recent years, China's energy-saving emission reduction target pressure is increasing day by day, and building energy-saving is increasingly attracting attention from all walks of life. At present, building energy consumption accounts for about 30% of the total energy consumption of the entire society. In high-energy-consumption buildings, the heat loss of walls and windows accounts for 85% of the total heat loss of buildings. To achieve building energy efficiency, we must improve the insulation properties of the external walls. In China, organic building insulation materials have gradually emerged in recent years and market share has increased year by year.

In January 2013, the "Green Building Action Plan" promulgated by the General Office of the State Council proposed to vigorously develop energy-saving, environmental-friendly and low-carbon green buildings, and complete the construction of 1 billion square meters of new green buildings during the 12th Five-Year Plan period; by the end of 2015, 20% of newly-built buildings in cities and towns meet the requirements of green building standards; in 2020, the proportion of urban green buildings in newly-built buildings will increase to 50%.

“According to the basic goals of China’s building energy conservation development and promotion of green buildings, 65% of building energy efficiency design standards have to be achieved for new buildings. At present, Beijing, Shanghai and other places have increased this standard to 75%, and other cities are actively following up. This has brought opportunities for the development of organic insulation materials with higher insulation performance. In addition, the number of existing energy-conservation reconstruction projects in various cities has recently increased. Currently, many cities in China have launched government-led energy-saving reconstruction projects for existing buildings. The old and old buildings were resurfacing insulation materials. In this area, the organic insulation material occupies a mainstream position as a whole,” said Li Jianbo, deputy secretary-general of the China Polyurethane Industry Association.

Flame retardant compliance is the key

“Polystyrene and polyurethane foams have inherently flammable properties. To use them as insulation materials, it is necessary to add flame retardants in order to achieve the corresponding flame-retardant grades. At present, most materials on the market have not been subjected to appropriate flame-retardant treatment. The flame-retardant performance cannot reach the flame-retardant standard required by the building's fire protection regulations at the moment,” said Professor Zhou Zhengyi, secretary-general of the China Flame Retardant Society.

Both industry experts and business representatives generally believe that the rational application of fire-retardant materials is the most important technical means to ensure fire safety. In fire safety, fire-retardant materials play a role in source control.

In fact, China's flammability rating for building materials is expressly stipulated, and the grading standards are still increasing. The "Code for Fire Protection in Building Design" (GB50016-2014), which began to be implemented on May 1st this year, is the original "Code for Fire Protection of Building Design" (GB50016-2006) and "Code for Fire Protection of High-rise Civil Buildings" (GB50045-95). It has been integrated to supplement the fire protection requirements of the building insulation system. The requirements for residential buildings are: when the building height is greater than 100m, the combustion performance of the insulation material should be Class A; when the building height is greater than 27m, but not more than 100m, the combustion performance of the insulation material should not be lower than Class B1; the building height is not When it is more than 27m, the burning performance of the insulating material should not be lower than B2.

"If we strictly follow the requirements of the code, the products are in compliance, construction is legal, and the vicious fire accident inside the building can be completely avoided. At present, the domestic fire-retardant technology and products have no problem at the technical level," said Zhou Zhengyu.

A typical example can fully explain the important role of fire-retardant materials in fire safety. In July 2013, in the Asian and Asian Games in San Francisco, USA, thanks to the strict flame-retardant standards implemented by Boeing and the extensive application of flame-retardant materials on the airframe, 304 passengers out of 307 passengers escaped and escaped. More casualties. “It is conceivable that the consequences of this catastrophe will be catastrophic if there are no strict flame retardant standards and widespread use of flame-retardant materials,” said a technician from a flame retardant company.

However, the construction industry is not optimistic. The CEO of a polyurethane insulation material production company stated that the price difference between fire-retardant materials and non-flame-retardant materials is 10% to 30%. Both the developer and the material supplier are unwilling to undertake this part of their own initiative in the interest of their own interests. The cost comes out. As a result, some unscrupulous companies cut corners and materials, use false pretenses, and shoddy products, and because of poor enforcement and inadequate supervision, some developers can save the province, even if they use inferior materials, so long as there is no accident, everything will be fine. In view of this situation, a large number of inferior and unqualified flame-retardant materials flooded the market, which not only disrupted the market order, but also caused great fire hazards to the buildings.

Zhou Zhengxuan also stated that the Chinese Flame Retardant Society once made a calculation. According to the market demand for flame-retardant plastics and the consumption of flame retardants, it is estimated that the proportion of flame-retardant plastics in developed countries in Europe and America is about 10%, while the Chinese fire-retardant plastic The proportion is less than 3%, and the application of fire-retardant materials in China is still far from reaching its due level.

Infringement of products into the heart of suffering

Although the thermal insulation performance is superior, how to ensure fire safety is also an issue that organic insulation materials cannot avoid. The products of the construction market were shoddy, and the illegal use and construction caused many fire accidents related to organic insulation materials.

On the evening of February 9, 2009, a fire broke out at the CCTV Television Cultural Center under construction. Afterwards, the court found that the exterior wall insulation material used shoddy plastic extruded board, and the related responsible persons constituted the crime of selling inferior products.

On November 15, 2010, a high-rise apartment building in Shanghai that was undergoing energy-saving renovation of the external wall caught fire, causing 58 deaths and 71 injuries. The accident was caused by the illegal operation of the unlicensed welder and the ignition of flammable materials such as unqualified polyurethane insulation.

On June 3, 2013, a fire and explosion occurred at the main building of Jilin Baoyuanfeng Poultry Industry Co., Ltd. in Changchun City, Jilin Province, killing 121 people and injuring 76 people. Afterwards, it was ascertained that the polyurethane insulation material used in the plant was a flammable, unqualified product.

Recently, a fire accident occurred at Kangland Old Age Apartment in Lushan County, Pingdingshan City, Henan Province, which exposed the problems of production and business units using color steel plates that used flammable combustible materials as their core materials and had low fire resistance. After many fires, organic thermal insulation material also suffered from policy bans and then lifted the ban.

“To tell the truth, now that we have heard of a fire accident, we have nervous nerves. I am afraid that the organic insulation materials are even more relevant. I’m even more afraid of the illegal operation and shoddy operations of development units and construction units. Enterprises and the entire industry are involved," said Gao Chunqing, chairman of Langfang Huayu Innovation Technology Co., Ltd., a polyurethane insulation board manufacturer.

"You can't put the board on the material manufacturer because of problems with the development and construction organization." When it comes to this issue, the person in charge of an organic insulation material production company feels very annoyed. Taking Jilin Baoyuanfeng Poultry Co., Ltd. as an example, the roof of the main plant is designed to use Class A rock wool as the insulation material, but the actual use of Class B3 polyurethane foam does not meet the “Building Design Code for Fire Protection” and is not lower than Grade B2. Provisions: The use of B3 polyurethane foam as insulation material for roofs and walls of cold storage does not meet the requirements of the Cold Storage Design Code that are not lower than Class B1.

"These fire accidents are caused by the use of substandard products. Simply raising the standards will not solve the problem and will make the enterprises at a loss," said Gao Chunqing.

Many industry insiders including Li Jiapeng also stated that developed countries such as Europe and the United States have used polystyrene and polyurethane foam as insulation materials for buildings for more than 30 years, but there have been no vicious fires caused by building insulation materials. The accident was reported.

Strengthening supervision is a top priority

Many people in the industry have responded that fire safety must be ensured and building energy conservation must be up to the standard. How to balance these two aspects is the key to related departments strengthening supervision.

“Now, the final focus of many fire accidents is on flammable and flammable foam insulation materials, and it is considered to be one of the main causes. After the incident, the local management authority did a great deal of work without exception. Investigations on buildings, construction sites, and materials have become a 'normal' as they have become a 'normal'. In fact, relevant departments should strengthen supervision at the beginning of construction.” Beijing Qidi Zhuoneng Building Information Technology Co., Ltd. Director Tao Xiao believes that after the accident, in addition to severely punishing the personnel involved in the accident, it is also necessary to exert pressure on the system and implementation, increase the prior supervision, and eliminate the organic insulation material market.

It is understood that the current "Code for Fire Protection in Building Design" (GB50016-2014) and the "Notice on Further Strengthening the Supervision and Administration of Fire-fighting Safety of Color Steel Plate Construction" and other provisions of the Ministry of Public Security require clear requirements for personnel-intensive places such as **, nursing homes, and construction sites. The insulation system should use Class A materials. At present, there are mainly color steel plates of the A and B standards on the market. The interlayer fillers of type A color steel plates are generally non-combustible and flame-retardant materials such as rock wool and mineral wool, and the main filler of type B color steel plates is polystyrene. , polyurethane foam. Due to the high cost of A-type color steel plate filling materials, the processing is more difficult and the price is higher. The B-type color steel plate is relatively inexpensive and, in addition, its lighter weight and easier installation and installation. Because of these characteristics of the B-type color steel plate, it is accepted by more construction and use units and used more widely. Therefore, although the application of B type color steel plate has strict restrictions, in practical engineering applications, because many color steel plate buildings belong to temporary structures, or are covered by surface decoration after construction and installation, it is difficult to find and supervise, resulting in The illegal application of Class B color plates is very common, and serious safety hazards are buried.

“The rock wool color steel plate not only has poor strength, but also costs 200-300 yuan per square meter. It is more than twice as much as polyphenyl color steel plate, and the installation cost is also very high. Therefore, many temporary building core materials still use organic insulation. Materials," said one industry insider.

In general, the inspections of the fire department focus on formal public buildings and commercial buildings, because these buildings must have relevant procedures of the fire department when the construction is completed and put into operation. However, it is difficult to cover the use of thermal insulation materials for some existing buildings and for some institutions and individuals to take private buildings.

“The State Council's order to investigate the illegal use of polystyrene and polyurethane foam is very necessary. We hope that this type of market supervision can be normalized, further purify the organic insulation material market in China, eliminate low-cost bids, and allow organic insulation materials to provide insulation and energy saving. The role of the firewall can also have the effect of the firewall.” Lin Yongfei, president of the Polyurethane Special Committee of the China Plastics Processing Industry Association, expressed the same view.

Must seize the source of a multi-pronged approach

According to Li Engine, former director of the Institute of Building Fire Prevention at the Chinese Academy of Building Research, the fire prevention problem for external insulation of external walls can be improved by improving the combustion performance of insulation materials and increasing the fire protection measures of exterior insulation systems. The approach should be to take the form of fire protection. Most of the fires in existing external wall thermal insulation projects in China have occurred during the construction process. The main reason is that the fire safety management measures at the construction site are not in place. To this end, it is necessary to distinguish between different circumstances, according to the situation and structure of external insulation materials of different systems, and accordingly take scientific, appropriate, and effective fire protection construction measures to improve the fire protection performance of exterior insulation systems as a whole.

According to industry sources, there is a quality problem in the insulation materials project and it is crucial to determine the bottom line as soon as possible. It is not objective to attribute the project quality problem to the material company alone. The construction quality problem of the construction industry is caused by the low bid and the insulation material industry is no exception. Among them, the general contractor bids at a price lower than the cost, after transferring the bid, the contradiction is transferred to the subcontractor, and then the analogy is ultimately borne by the material company. Such an approach is particularly common.

Zhu Changchun, secretary-general of the China Polyurethane Industry Association, believes that developers and construction companies should be aware of the bottom line of the insulation material industry when purchasing. However, at the current stage, the bottom line of thermal insulation products has not been done yet. If there is no quality or price floor, even if there are strict standards and regulations, the accident cannot be prevented. Therefore, it is necessary to carry out effective and long-term supervision under the management and promotion of the government, formulate industry minimum guidance prices, promulgate industry management methods, establish industrial quality credit system, and promote the healthy development of the industry.

In addition, the current inspection system for building insulation materials has also been widely criticized by the industry. How to ensure the consistency between the sample submitted for inspection and the sample on the wall is also a problem that needs to be solved by the relevant departments.

“For government agencies, the first is to strictly limit the production and application of flammable organic building insulation materials; the second is to modify and improve the relevant technical specifications; the third is to strictly control the fire inspection and acceptance of construction projects, the new construction, temporary Buildings should strictly follow the standard requirements, control non-flame-retardant materials, sampling sampling inspection; Fourth, in the fire supervision and inspection, for the use of materials that do not meet the requirements, should be carefully checked, should be replaced within a deadline or to do fire prevention treatment.” Zhu Chang said.