Solutions to prevent house fires

Many existing problems

Dr. Cao Duy Khoi - Deputy Director of the Vietnam Institute of Building Science and Technology (IBST) said that through the general inspection of the Ministry of Public Security , reviewing nationwide about 1.2 million constructions, there are about more than 38 thousand existing constructions that do not ensure fire safety, these are constructions that are very difficult or impossible to fix.

The largest violation rate is about escape, accounting for 35%, while this is the number 1 core requirement of fire safety. Constructions violating the second core element of fire safety, preventing fire spread, account for 21%.

Fire prevention and fighting measures need to be taken in every household. Photo: Minh Phuong

Thus, the two most important fire safety factors alone accounted for more than half of the total violations (56%). In addition, 20% of constructions violated standards on fire prevention and fighting equipment (PCCC), fire alarm and fire fighting systems.

Citing real-life examples, the IBST leader gave a typical example of the fire in a mini apartment building in Khuong Ha (Thanh Xuan, Hanoi ). This building is located in a deep alley, with no road for fire trucks to access.

The apartment building was built with 9 floors and 1 attic; the actual construction area was about 270m2, 3 floors were built without permission and exceeded the area. According to the typical floor plan, in the middle there is a very small corridor, surrounded by densely arranged apartments, surrounding the elevator and stairwell area.

The house has air vents and stairs running through all floors, from the first floor is the parking lot, up to the rooftop which is the 9th floor. These air vents are the main cause of many deaths.

When the fire broke out in the first floor parking lot, the house had only one escape route to the alley in front because the fire generated a lot of smoke and heat, and all the smoke and heat were concentrated through the vents to the upper floors.

Regarding the fire at 4 Hang Luoc (Hoan Kiem, Hanoi), through the typical floor plan, it can be seen that the first floor is the sales area outside, with stairs inside leading to the upper floors. The second floor is the warehouse area, also with stairs leading to the upper floors. The third and fourth floors are the family living space.

The fire broke out early in the morning, when everyone was asleep, so there was no time to react. When the smoke was discovered, only an adult woman was able to climb over the balcony to the balcony of the house next door to escape. The two elderly people and two children, because they could not move to this emergency exit, died in the fire.

"Existing housing is diverse in types and fire hazards, especially with individual houses combined with businesses that violate basic fire safety factors such as escape and fire prevention. Fire safety problems are often serious and difficult to overcome for many reasons (difficult to overcome or inability to overcome fire safety; infrastructure does not meet requirements...) while the golden time to escape is usually 5 minutes, maximum 10 minutes" - Dr. Cao Duy Khoi said.

Fire prevention during construction

Fire safety is a very important issue in construction design, which has been legalized in regulations and standards. From a design perspective, architectural plans with reasonable fire exits and fire escapes are important and prerequisite conditions to minimize risks when an incident occurs.

Next, the fire alarm and fire fighting system must be scientifically designed, up to standards, and convenient to operate. From a construction perspective, items related to fire prevention and fighting must be done according to the design, ensuring professional quality.

However, effective fire prevention and fighting not only depends on architectural components but also on construction materials, including structural materials, refractory materials, structural solutions, architecture and interior.

The better the fire resistance of the solution, the more it limits the occurrence of fire; or if a fire does occur, it reduces the possibility of spreading, prolongs the fire resistance time for easy escape, and ensures human safety.

Associate Professor Dr. Chu Thi Binh - Hanoi University of Architecture said that all projects when designed, constructed and used in Vietnam must ensure fire safety requirements.

Thus, in the design of construction structures, in addition to designing structures to ensure load-bearing conditions and normal use, it is necessary to design structures that satisfy fire-resistant conditions.

However, Vietnam has not yet had any instructions for calculating and selecting fireproof protective layers for steel structures, but there are some tables for steel columns and beams covered with mortar, concrete or specialized fireproof panels. The number of tables and types of materials in the tables are limited. There are no tables for fireproof mortars and fireproof paints.

Meanwhile, Europe has a full range of regulations and standards related to the design of building structures to ensure fire safety conditions, with fire-resistant structural design standards parallel to structural design standards at normal temperature conditions.

Therefore, it is very necessary to study European standards to serve the compilation of the new-oriented Guide to Design of Fire-Resistant Steel-Concrete Composite Structures.

"It is possible to apply calculations to design fire-resistant steel structures according to European standards, American standards or Russian standards. However, testing is still needed to determine the thermo-physical properties of fire-resistant protective covering materials to have data to include in structural calculations" - Associate Professor, Dr. Chu Thi Binh said.

Associate Professor Dr. Nguyen Truong Thang - Hanoi University of Civil Engineering said that fire-resistant structural design is a passive measure and the last line of defense to protect a building from collapsing in a fire, when other proactive measures in planning, architecture, electromechanics... are no longer effective.

Along with QCVN 06, the reality requires an early TCVN for design of fire-resistant reinforced concrete structures. Drafting TCVN for design of fire-resistant reinforced concrete structures according to SP 468.1325800.2019 is reasonable in the short term due to its interconnectivity and systematic nature with QCVN 06 and TCVN 5574:2018 for normal temperature.

"In the long term, the transition to European standards is also favorable because Russian standards and European standards have many similarities. The guidance document for designing fire-resistant reinforced concrete structures needs to be drafted together with TCVN. More experimental research is needed to verify the standards in Vietnam's conditions" - Associate Professor, Dr. Nguyen Truong Thang informed.

 

Based on the current reality, houses or buildings have two main structures: reinforced concrete and steel. Each structural position has a fire resistance time regulation. Therefore, the structure of the structural layers to ensure fire resistance needs to be paid attention to and the load-bearing capacity needs to be calculated specifically and scientifically.

Dr. Le Quang Hung - former Deputy Minister of Construction, Chairman of Vietnam Concrete Association

Source: https://kinhtedothi.vn/giai-phap-ngan-ngua-hoa-hoan-nha-o.html