What is special about gas explosion? Why have restaurants become heavily affected areas?, High density flash explosion 2 deaths and 2 injuries process | Gas | Restaurant

This morning, a gas flash explosion occurred in a street house in Gaomi City, Shandong Province, resulting in 2 deaths and 2 minor injuries. Although the cause of the flash explosion is under investigation, frequent gas safety accidents have sounded the alarm for gas safety in recent years. How can ordinary citizens and non resident users effectively prevent it? The Municipal Commission of Housing and Urban Rural Development and the Gas Company have provided clear instructions.

The flash explosion power is relatively small

According to reports, at around 7:15 am today, a flash explosion occurred at the Quanfu Yuan Banbian Tian grilled fish restaurant on Fenghuang Street and Jiafang Road in Chaoyang Street, Gaomi City. The monitoring records show that at the moment of the explosion, thick smoke spewed out from the street, and the shock wave flew out with broken building materials, colliding with some vehicles. The glass of the street facing merchants has all shattered, and the ground is piled with a large number of bricks, tables and chairs, demonstrating the power of the flash explosion.

In fact, since the beginning of this year, gas flash explosions and explosions have occurred in many places. On June 14th, a flash explosion occurred in a residential area in Chifeng, Inner Mongolia, resulting in 2 deaths and 4 injuries. The glass of multiple buildings was shattered by the earthquake. Just a few days later, a gas explosion occurred at Fuyang Barbecue in Xingqing District, Yinchuan City. The store manager Hai and staff member Li violated relevant safety management regulations by replacing the pressure reducing valve connected to the liquefied gas tank without authorization, resulting in a rapid leakage of liquefied gas in the tank and causing an explosion, resulting in 31 deaths and 7 injuries, with particularly serious consequences.

According to the explanation of the emergency management department, flash explosion usually refers to flammable and explosive gases that accumulate in a relatively enclosed space with no air circulation to a certain concentration. Once they encounter an open flame or electric spark, they will immediately ignite and undergo an explosion reaction. The volume of the gas will instantly expand to a larger proportion. In general, flash explosions only occur once.

The explosion limit of natural gas is 5% -15%, and the explosion limit of liquefied petroleum gas is 1.5% -9.5%. In the process of using gas at home, if there is a gas leak, the explosions that occur are mostly flash and detonation. However, compared to explosions, the power of flash explosions is relatively small. If flammable and explosive gases can be replenished, multiple explosion accidents will occur.

Under what circumstances will gas explode and catch fire? According to personnel from Shanghai Gas Co., Ltd., the gas flowing in natural gas pipelines or canned gas is very safe without strong damage. Generally speaking, a gas explosion requires three elements to ignite: gas leakage, reaching explosive concentration, and encountering an ignition source.

It is understood that gas leaks are prone to occur at the joints of gas valves, gas stoves, gas meters, and gas hoses. Improper use of gas appliances can also cause leaks. For example, using gas appliances that have exceeded their service life may also result in gas leaks due to aging or loosening of components. Due to the fact that the main component of natural gas is methane, high or low methane concentrations in the air generally do not cause explosions, but when they fall between the two, they may cause explosions.

When gas leakage is within the explosive concentration range, including but not limited to the following situations, it is possible to cause an explosion, such as open flames, sparks, and other high-temperature ignition sources.

Restaurants should install gas alarm linkage devices as soon as possible

Compared to ordinary households, non residential users are particularly important for gas safety due to factors such as high gas consumption, complex operators, and dense personnel in the premises. Once an accident occurs, the impact will be more severe.

Last June, the Shanghai Municipal Commission of Housing and Urban Rural Development issued a notice requiring natural gas users in the catering industry in the city to immediately carry out the selection, installation, and acceptance of gas alarm devices and linked shut-off valves. In February of this year, the Shanghai Municipal Commission of Housing and Urban Rural Development issued a notice on the replacement of gas appliance connecting hoses by existing pipeline natural gas residential users in this city, requiring them to replace the rubber hoses connecting gas appliances with ultra flexible gas appliance connecting hoses. The series of notices issued are aimed at effectively eliminating gas safety hazards and further ensuring the safety of gas users.

To ensure the safety of gas usage for non residential users, in addition to regular security checks provided by gas companies, users also need to have dedicated personnel responsible for the safety and use of gas, including daily safety inspections of gas plants, familiarity with the condition of gas equipment and facilities, regular maintenance and upkeep of gas equipment, or commissioning gas enterprises or qualified units to modify, relocate or dismantle gas facilities when necessary, and handling corresponding procedures with relevant gas enterprises.

Shanghai Gas also stated that it is strictly prohibited to live in kitchens and rooms with gas meters and equipment. It is strictly prohibited to mix two gases, that is, only one gas source is allowed to be stored or used in the same gas field, and other fuels cannot be placed in the room where natural gas pipelines are installed at the same time. At the same time, fire extinguishing equipment should be placed near the gas consumption point and regularly maintained, maintained, and updated. If gas is used in indoor public places, underground or semi underground buildings, gas leakage safety protection devices should be installed and used to ensure its normal use.

Due to the fact that fires in gas plants are often caused by leaks in gas equipment and facilities, unauthorized personnel leaving the kitchen during cooking, improper use by operators, and failure to clean oil stains in a timely manner, Shanghai Gas suggests that in the event of a fire caused by the above situation, the main valve in front of the gas meter should be immediately closed, and then the fire should be extinguished with a fire extinguisher or fire blanket. When a gas explosion or flash occurs, the crowd should be evacuated as soon as possible, and the property and surrounding merchants should be notified. If conditions permit, the gas main valve should be closed in a timely manner to avoid further losses and reduce the possibility of secondary accidents.