The biggest difference between a negative pressure ambulance and the other two types of ambulances lies in the word "negative pressure", which simply means that the air pressure inside the vehicle is lower than that of the outside world, and the air will always flow from a place of high pressure to a place of low pressure, which ensures that viruses inside the vehicle will not pollute the outside world.
In fact, the principle of "negative pressure" is very simple, and is often seen and used in our daily lives. For example, if we use a straw to drink water, inhaling will create a low-pressure area inside the straw, and then the outside air pressure will press the water into our mouths. Another example is the formation of a typhoon, the eye of the wind is a low-pressure area, so the surrounding air is moving towards the eye of the wind, and the size of the wind depends on the size of the pressure difference.
First of all, what is a "negative pressure ambulance" and how is it different from a normal ambulance? Ambulance A, B, C three types, A type is the transfer ambulance, with basic first aid and nursing equipment; B type is a first aid vehicle, on the basis of the A-type increased a lot of emergency equipment, such as pressurized infusion equipment, chest decompression equipment, respiratory machines, defibrillators and so on. The negative pressure ambulance is of type C, mainly used to transport patients with high-risk infectious diseases, especially those that can be transmitted through the air, such as influenza and typhoid fever, in addition to this outbreak of the new coronavirus.
Compared with ordinary ambulances, what are the differences between negative pressure ambulances? First of all, the air inside the negative-pressure ambulance is in a negative state, that is, the air pressure inside the vehicle is lower than the normal atmospheric pressure, which allows only the air from outside the vehicle to enter the vehicle under atmospheric pressure, and then discharged after harmless treatment of the air inside the vehicle, which is safer.
We only look from the appearance, negative pressure emergency vehicles and ordinary emergency vehicles and not much difference, mainly in its internal structure, negative pressure emergency vehicles more than a set of negative pressure device. The device is located in the center of the car, similar to some of the barbecue store can be moved freely smoke pipe. It is the biggest difference with the general emergency vehicle is that, with the isolation of airborne disease function.
The air pressure inside the vehicle is less than that outside, so air can flow from the outside to the inside. The negative pressure device creates a fixed area of air circulation, and the air flows from top to bottom inside the vehicle, ensuring that healthcare workers get fresh air first, before the patient's exhaled air is filtered and absorbed. The filter is generally located at the patient's head position, which also ensures that dirty air is recovered first.
The design of the car, but also in the stretcher based on the addition of a more rigorous isolation chamber, but also independent of the negative pressure equipment, this isolation chamber fan using lithium battery power supply, can be used continuously for the health care workers to add a safeguard. Independent isolation compartment outflow of air directly into the air filtration system, for effective harmless treatment, to prevent harmful air outflow to the outside world caused by the harm.
In fact, the biggest feature of the negative pressure ambulance is that it can "isolate under negative pressure", which the conventional ambulance can't do at this point. The new, sudden infectious diseases to implement emergency treatment, including the transfer of patients with infectious risks, can be effectively isolated, and the harmless treatment of air inside the car, so that the outside environment from pollution, to prevent the further spread of the epidemic, mainly used for major infectious diseases, the safe isolation and transfer of patients. Especially for this new coronavirus epidemic, must use this negative pressure ambulance, can effectively isolate the infected.
In the end, the addition of negative-pressure ambulances more effectively protects frontline healthcare workers from the risk of infection during the transfer of patients in this pneumonia outbreak. It is also more effective in preventing possible contamination of the outside air and the spread of the pneumonia virus during the transfer process.