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Fire escape methods in chemical plants
1.Call fire police immediately. If the fire is at initial stage, should organize the fire fighting. Escape via various evacuation channels if necessary.
2.Escape from nearest way. For example, from nearest door or windows. If the door or windows are closed, should break it to escape.
3.Escape from water pipe. If all other escape channels are blocked after fire, you can choose to escape from water pipe outside of building. You can use clothing to make a string to escape.
4.If the fire floor is 2-3, you can throw out sponge cushion or rubbers, then slide down the wall to the sponge cushion.
5.If no way to escape, the trapped people should go to the platform outside and wave the arms to ask for help.
Escape Method for Leakage Accident in Chemical Plant
1.In case of leakage, operators on site should immediately stop operation and quickly evacuate the leak contaminated area. If the leakage is flammable and explosive, personnel should remove the explosives object in the accident area, extinguish the fire and cut off the power supply in time if it is possible. Personnel should lie down in place when explosion occurs before they can evacuate.
2.When evacuating, we should make clear the direction of poisonous gas flow, and evacuate to the windward side. We should not follow the direction of poisonous gas flow.
3.When evacuating, wet towels and masks can be used to cover the mouth and nose to protect the trachea.
4.When large amount of leaks occur, don’t panic, don’t be crowded, listen to the command, especially when there are more people, don’t panic, don’t shout, and evacuate calmly, calmly and orderly.
5.Timely treatment is needed for chemicals injury.
Skin contamination: Contaminated clothing should be removed immediately, washed with a large amount of flowing water, and contaminated hair should be cleaned.
For those who splash chemicals into the eyes, rinse them thoroughly and promptly. The rinsing time should be no less than 10-15 minutes. Do not rinse with hot water.
Inhalation of toxic gases through the respiratory system: should be immediately sent to the fresh air and rest quietly, keep the respiratory tract unobstructed.
Invasion of toxic substances through the digestive system: vomiting should be carried out as soon as possible. If taking corrosive poisons by mistake, the digestive tract can be protected by drinking milk, egg white and vegetable oil orally.
6.Cardiopulmonary resuscitation (CPR) should be performed immediately after the patient has been rescued from the poison site but the heartbeat and breathing stop. Rescuers should take precautions against poisoning during artificial respiration. For example, before mouth-to-mouth artificial respiration for hydrogen sulfide poisoners, cotton or handkerchief soaked in salt solution should be used to cover the mouth and nose of the poisoners.

Fire and explosion accidents often occur in chemical plants, causing serious damage to enterprise production and society. Some fire and explosion accidents occur repeatedly. For example, Water shortage caused boiler explosion accident, gas jacket and drum suffocation explosion accident, transforming saturated hot water tower explosion accident, synthetic tower internals damage and ammonia tank explosion accident, etc.
Reasons for chemical plant fire and explosion are as below:
1.Leakage of combustible gas.
A.Gas leakage from dynamic and static seals of equipment
B.Gas leakage from Equipment Corrosion Pipeline
C.No water in water seal and gas leakage occurs
D.Gas leakage due to defect or rupture of valve in equipment pipeline
Such accidents are mainly caused by improper management of production equipment, poor material quality or maintenance of sealing materials, improper operation and maintenance, no pressure relief but add additional force during maintenance, not operate according to procedures regulations for starting and stopping of inspection, etc.
It must be managed in accordance with the relevant regulations such as the stipulated overhaul operation rules, the standards of leak-free factories and the regulations on power management of equipment. To detect and eliminate leaks in time, preventive measures should be taken to avoid enlargement or disaster accidents.
2.System at negative pressure, air and combustible gas mixing
A.When the system stops, negative pressure and inhalation of air will occur as the temperature drops after stopping.
B.The system is shut down and water cut off. After shutdown, the water seal loses its function due to leakage, resulting in air inhalation.
C.Operation error, improper connections, incomplete or failure of alarm interlocking devices, resulting in unbalanced gas pumping causes negative pressure, air suction occurs from the open or leakage.
D.The gas inlet pipeline is blocked by debris, crystals or water, causing negative suction and inhaling air from an open or leaky place.
E.When air is used for pressure test and leak test, the combustibles in the system are not cleaned up and no blind plate is added, resulting in the mixture of combustible gas and air.
Most of these accidents occur in gas transmission or gas compression related positions. When they occur in the process of pressurization, they are more dangerous, because in explosive mixtures, on the one hand, the oxygen content is increasing, on the other hand, after pressurization, the explosion limit range is enlarged, and accidents are more likely to occur.
3.Oxygen content exceeding standard rate in system production
Oxygen content exceeding the standard rate may occur in many parts, but the reasons are mainly concentrated in the gas-making positions, which are usually caused by operational errors, equipment defects, personnel violations, oil breakage, steam breakage or failure of safety alarm devices. Oxygen content exceeding the standard rate may occur in areas such as desulfurization, transformation and compression, which should be paid special attention to.
4.System convergence
A.High-pressure gas blows to low-pressure gas, forming over pressure explosion
B.Chemical explosion caused by mixture of air and combustible gas
The former is mostly due to operational errors and failure of low-voltage safety accessories or accessories. For example, the explosion of synthetic high-pressure series and low-pressure liquid ammonia tank, the explosion of synthetic high-pressure series and low-pressure regeneration system, etc. The latter is mostly due to the error of blind plate plugging, which is caused by valve replacing blind plate or miss-operation. If a device is on fire, there is air inside. Because the system is not isolated by blind plate, the flammable gas leaks into the valve or someone’s misoperation to the closed valve, which causes the flammable gas to enter the equipment under fire and mix with the air to form explosive mixture gas, thus explosion occurs.
5.Fire work not in accordance with rules
A.Private fire work without fire certificate and fire safety knowledge
B.Although the application for fire certificate is get, but not completely replaced or the sampling method is incorrect, the analysis result is wrong.
C.Poor consideration of fire safety measures
D.Safety conditions of the scene for fire work is not carefully checked
E.Fire system is not completely isolated from other systems
F.Self change of safety measures or time of fire operation certificate
G.Non-replacement or non-maintenance positive pressure ignition
Such accidents are the most of chemical fire and explosion accidents. As the fire operation is highly technical and requires high management, the safety and technology departments should effectively control it in order to prevent accidents.

Preventive Measures for Fire and Explosion Accidents
Control and Eliminate Risk Factors
1.One is reasonable design. In the process of design change, advanced technology and high-level, reliable fire and explosion protection measures should be adopted, and safe technological specification and reasonable piping should be adopted.
2.Another is correct operation and strict control of process indicators. The technical regulations for safety production in chemical enterprises are the summary of the experience of safety production for many years. As long as we strictly follow the regulations, strictly control the process indicators, exceed the limits of the indicators within the scope prescribed by the regulations, and take effective measures to reverse them immediately, instead of reluctantly maintaining them, the anticipated safety results can be achieved.

On the fire regulation, there are some equipment should be automatically controlled by fire alarm control center. They are fire pump, smoke exhausting fan, fire proof door and fire curtain. The fire pump and smoke exhausting fan can not only be automatically controlled by fire alarm control center, but also be directly controlled manually at spot. Manual control buttons should be set on both sides of the fire rolling curtain on the evacuation channel.
Why do these devices so important for fire fighting? These devices can extinguish early fire and prevent fire spreading. So, these devices should be automatically turned on or shut off immediately when fire occurs.

On the fire regulation, other devices are not required to be set as automatically controlling. For example, fire bell horn and fire broadcasting etc. should be manually triggered or linkage output triggered after confirmation or other signal is found. If fire bell and fire broadcasting goes off without confirmation, it may cause unnecessary fear for people if false alarm occurred.
In the water extinguishing system, the fire hydrant system is controlled by the fire hydrant button, the start button on the control center linkage controller and the pump button on the pump control box of the pump room. Any button of these three ones is pressed, it will start the fire hydrant pump. It is manually controlled and not automatically controlled. There may have automatic and manual mark on the state switching switch of the control cabinet in the pump room. The automatic here means started by remote controlling and manual means started by local controlling. In an automatic sprinkler system, there are automatic and manual mark on the control cabinet of the sprinkler pump in the pump room. “Manual” means “on-site start” and “automatic” means manual start-up of the pump or pressure switch on the wet alarm valve of the control center. For the whole sprinkler system, “automatic” refers to the pressure switch start-up, and “manual” refers to the control center remote control start-up.

For pipe network gas fire extinguishing system, the release of fire extinguishing gas must be confirmed by people on the scene. Automatic state of fire identification is equipment confirmation. Its general practice is two sets of detectors at the same time issued alarms, can be considered as a fire start signal. When the first set of detectors alarm, the personnel on duty should immediately rush to the scene to make a manual confirmation on the spot to decide whether to start the fixed fire extinguishing system. Although there are automatic and manual start-up modes in the design, manual start-up mode should be the main one when someone is on duty.
So the fire control center panel only displays the manual automatic working state of the system. It monitors the system of alarm and injecting feedback signals at various stages, and controls other linkage devices such as fireproof doors and windows, air conditioning and fireproof valves. But it is not required to immediately start off the fire extinguishing system. This is to ensure the reliability and accuracy of the system.