【Haichuan Fire Safety Discussion】Are you aware of the fire hazard posed by kitchen smoke ducts?

A staff member at Zhao Yuanwai Restaurant said that the fire was caused by improper handling by the kitchen staff, which led to an open flame entering the flue and triggering a fire. “At that time, there were four or five tables of customers eating in the shop; upon seeing smoke coming from inside, they all left. Later, the staff at the restaurant put out the fire, and when the fire department arrived, their main task was to remove the smoke. ”A staff member said. “The store suffered significant damage; the walls and floors were badly affected by the smoke, and the wooden stairs were also damaged as a result of it. ”Another staff member said.

Fire safety in the kitchen cannot be taken lightly; the Beijing Fire Department advises paying special attention to safety measures related to smoke exhaust systems. After analyzing past domestic grease duct fires, the Beijing Fire Department has issued safety guidelines regarding such fires. Analyzing the causes of fires in flue ducts, it is found that most such fires occur because organizations and individuals fail to realize the importance of cleaning the flue ducts regularly and thoroughly. In order to cut costs and reduce operating expenses, they refrain from cleaning the flue ducts, or they clean them incompletely or at inappropriate times. It is caused by the accumulation of oil deposits in the flue, which is ignited when an open flame enters the flue. A specific analysis of the causes of fires in smoke exhaust ducts can be divided into the following two aspects. The first aspect is combustibles. Since the kitchen has to deal with coal and gas fires throughout the year, its environment is relatively harsh due to the special nature of this space. Under such conditions, the incomplete combustion products generated during fuel combustion, as well as the grease fumes resulting from oil vaporization, tend to accumulate in the grease ducts, especially at the corners of these ducts. If it is not cleaned in a timely manner, over time a certain thickness of grease will accumulate and adhere to the surfaces of the smoke ducts and the range hood. Since these oil residues are old oil that has accumulated over time, once a flame gets into the smoke duct, these residues will be ignited quickly, and the fire spreads very rapidly. The second aspect is the presence of a fire source. There are three possible sources of ignition inside the smoke exhaust duct: 1) The chef accidentally uses too much oil or handles it improperly while cooking, causing the oil pan to catch fire; under the strong suction force generated during the operation of the smoke exhaust duct, the flames are drawn into the duct along with the smoke; 2) Oil deposits inside the duct catch fire spontaneously, as the smoke drawn in is at a very high temperature, and these oil deposits undergo oxidation and self-ignition due to this high temperature; 3) Sparks or flames resulting from cutting the smoke exhaust duct during its disassembly.

Basic measures to prevent fires in exhaust ducts: 1. The design, material selection, and installation of exhaust ducts must be reasonable and in accordance with standards. There are currently no unified design, acceptance standards, or industry guidelines for the design and installation of flue systems in the food service industry, which has led to chaos in this field and created significant risks for the occurrence and spread of fires involving such flue systems. It should be designed and installed from the perspective of intrinsic safety. The designer should reasonably design the layout and geometric parameters of the flue, taking into account the specific conditions of the kitchen, the accumulation of grease fumes in the flue, and the spread of fire in the event of a blaze. The material used for the flue ducts should be non-combustible; ensure an appropriate thickness for the material, and if external covering is necessary, use a flame-retardant material. Pipelines should be designed with a certain slope, and oil drainage ports should be provided at the bends to facilitate the removal of oil deposits and other contaminants. 2. Standardize operational use and management, and clean the smoke exhaust ducts in a timely manner. Regularly clean the smoke exhaust ducts to ensure the quality of the cleaning. The flue should be cleaned every six months, and the electrical wiring should be inspected regularly. When frying food, measures must be taken to prevent the oil from spilling and causing a fire. After cooking is finished, turn off all gas and fuel valves in the kitchen promptly; only after cutting off the gas supply, heat source, and power supply can you leave. Strengthen fire safety inspections and education in the catering industry, paying special attention to areas such as fume exhaust systems. 3. Further promote the installation of standalone alarm devices, with increased efforts being made to install them among vulnerable groups such as the widowed, the orphaned, and those living alone.

Reported by He Lei, a reporter from Qinchu News Network: At around 5:30 p.m. today, a fire broke out in the flue on the kitchen balcony on the second floor of the Xiangxieer Hotel at Shiyan Railway Station. Employees and nearby businesses helped to extinguish the fire, and eventually firefighters arrived and put out the blaze. No injuries were reported as a result of the fire. At 5:38 p.m. today, a staff member at the small commodities wholesale market at Shiyan Railway Station saw thick smoke coming from the chimney outside the second floor of the Xiangxieer Hotel, indicating a fire. Many merchants have also noticed this situation, and the fire is still spreading. A witness said, “There is a parking lot behind the hotel. I saw fire coming from the chimney, rising straight up; the entire chimney, which is over ten meters tall, turned red from the fire.” ” Upon arriving at the scene, the firefighters promptly used high-pressure water guns to spray water in order to cool down the chimney and extinguish the fire. With everyone’s cooperation, the fire was extinguished at 6:07 that evening. Preliminary investigations indicate that the fire was caused by a fire in the smoke duct of the kitchen on the second floor of the Hotel Chancellors; fortunately, no injuries were reported.

A official from the Beijing Public Security Fire Department said that as of November 30, Beijing had received 67 reports of smoke coming from flues this year, 46 of which occurred in food service establishments. An analysis of these incidents shows that the main causes of flue fires include improper operations by kitchen staff, food service establishments failing to clean the smoke exhaust systems regularly in order to save costs, as well as a lack of responsibility and professionalism on the part of some companies responsible for cleaning such systems, resulting in irregular and inadequate cleaning of the flues. In response to this situation, the Beijing fire department issued a special notice requiring that for restaurants serving fatty foods such as Peking duck, the cleaning cycle for the smoke exhaust pipes in their cooking areas should not exceed 30 days; for other restaurants, this cycle should not exceed 60 days ； In the event of a fire in a food service establishment that results in significant losses or social repercussions, compulsory measures such as detention and administrative penalties shall be imposed in accordance with the law to hold the relevant persons accountable ； The fire department also requires the units responsible for cleaning grease traps to publicly commit to the timing, location, and quality of the cleaning work, ensuring that it is carried out in a standardized, professional, and responsible manner. The fire department will also remind food service establishments to conduct regular inspections and increase the frequency of cleaning as appropriate. The reporter learned that flue fires are often hidden in the early stages and difficult to detect; by the time they are noticed, the best opportunity for extinguishing the fire has usually passed, leading to an escalation of the blaze. Under the effect of the chimney effect, once a fire breaks out in a flue, it often spreads rapidly. Since flues are usually narrow and enclosed, this makes it difficult to extinguish the fire, and it can lead to multiple fires or fires that occur in different levels. (End)

“There's a fire! Hurry and put out the fire. ”At around 10 a.m. on the 3rd, a fire broke out accidentally at a cafeteria near the Shamaojing section of the Southwest Ring Road in Guiyang. Within just one hour, it spread to nearly 1,000 square meters of prefabricated structures as well as a car wash. Fortunately, firefighters arrived in time to put out the fire, preventing any casualties. Just after 11 a.m. yesterday, reporters arrived at the scene and saw a row of prefabricated shelters set up by the road on fire; the flames reached a height of nearly 2 meters, and crackling sounds could be heard coming from inside the shelters from time to time. Firefighters nearby are working hard to put out the fire. Witness Ms. Tang said that the mobile shelter where the fire broke out was a canteen belonging to an organization. Around 10 a.m. that day, they first saw black smoke coming from the chimney of the canteen; shortly after, fierce flames erupted, and people ran out of the canteen. Seeing this, everyone picked up their phones to call the 119 fire emergency number. Soon, 3 fire trucks arrived at the scene of the fire. The firefighters promptly began to extinguish the flames in the temporary shacks on fire. However, due to the intensity of the fire, it took nearly half an hour to bring the flames under control. After the fire was extinguished, reporters went to the scene and found that the cafeteria that caught fire was a temporary structure with a steel frame; its walls were made of flammable materials, and there was also a lot of wooden material used for decoration inside. The area affected by the fire was almost completely destroyed. Additionally, a small merchandise store was also set on fire; once again, the goods inside were almost completely destroyed. By visual estimation, approximately 1,000 square meters of area was burned down.