The development and application of positive pressure air respirators.

Introduction to Air Breathing Apparatus

In the 1830s, frequent fire disasters and coal mine accidents led to an increase in miner deaths due to various harmful gases, resulting in property losses. To ensure the safety of workers, the air breathing apparatus was invented.The air breathing apparatus is a self-contained open-circuit breathing apparatus, widely used in firefighting, chemical industry, shipping, petroleum, metallurgy, warehouses, laboratories, and mines, allowing firefighters or rescue personnel to safely and effectively perform firefighting, rescue, and medical assistance in environments with smoke, toxic gases, steam, or oxygen deficiency.

Development History of Air Breathing Apparatus

First Stage:

From the mid-19th century to the 20th century, the research and application of air breathing apparatus became a product that emerged in response to needs. At that time, China was implementing foreign reform and development policies, with increasing international exchanges. Our country's firefighting, coal mining, and petrochemical systems introduced many relatively advanced air breathing apparatuses. The air breathing apparatus at that time was a negative pressure type (the pressure inside the mask is lower than the environmental pressure). The gas cylinder was made of steel, with a specific gravity of 1.1 to 1.2 and a charging pressure of 20MPa, resulting in a large volume, inconvenient carrying, and a short effective use time.

Second Stage

From the early 20th century to the 1980s, the air breathing apparatus was in a developing stage, during which the self-contained positive pressure air breathing apparatus was invented. By the 1950s, air breathing apparatus had been equipped in municipal firefighting.

Third Stage:

Since the end of the 20th century, the development of air breathing apparatus has reached a mature stage. The material selection for air breathing apparatus has reached new heights, with chemical resistance and high-temperature resistance becoming the main material choices for masks. Fire-resistant and flame-retardant materials have been widely applied to the fabrics of air breathing apparatus. With the extensive use of new technologies, new materials, and new processes, carbon fiber fully wrapped aluminum alloy composite gas cylinders have emerged in China. Its birth has reduced the weight of the entire positive pressure air breathing apparatus set by 30%, effectively reducing the workload of firefighters and rescue personnel, ensuring the smooth progress of firefighting and rescue operations. The Fire Department of the Ministry of Public Security promptly issued a notice to replace the carbon fiber fully wrapped aluminum alloy composite gas cylinders.

Fourth Stage:

Entering the intelligent 21st century, air breathing apparatus has been widely used in various places and fields to cope with more complex environments. However, there are still many aspects that do not meet usage requirements, which further promotes the development of air breathing apparatus, product optimization, exquisite material use, and further improvement in pressure reduction in gas paths, while also incorporating more intelligent functions, such as rescue functions and the application of electronic technology in air breathing apparatus products.

The following are new technology applications for air breathing apparatus:

1. Communication System:

With the application of electronic technology, the issue of masks obstructing normal voice communication has been resolved.

As we all know, the air breathing apparatus is worn on the head of the worker through a mask, thus protecting the mouth, nose, and face. Although it protects the face, normal communication is obstructed. Therefore, the air breathing apparatus has developed a communication function, with the mask equipped with an electronic amplification device and voice communication device, which can connect to many brands of walkie-talkies, amplifying the wearer's voice at close range and enabling remote Bluetooth communication for long-distance voice calls.

2. Electronic Display Function (HUD)

With the development of electronic technology and software, the air breathing apparatus has evolved into an intelligent air breathing apparatus system. A pressure display system (referred to as HUD) has been added inside the mask. This device uses red, yellow, blue, and green LED lights for display, consisting of a pressure display device and a Bluetooth transmission device, allowing real-time observation of the remaining pressure in the gas cylinder, remaining usage time, current environmental temperature, and battery power, while also having a fall alarm function.

3.Fast Charging Function

 After each accident, rescue time is critical, but the situation in accidents is often unpredictable, causing delays. Insufficient gas cylinder pressure can pose dangers to both workers and rescued individuals. The air breathing apparatus carries a limited amount of 30MPa of air, and in special situations, frequent gas cylinder replacements are necessary. However, the cumbersome steps for replacing gas cylinders waste a lot of rescue time. With the continuous improvement and development of technology, the air breathing apparatus has achieved a rapid inflation device similar to an "airborne refueling aircraft," which allows for quick refilling of gas without disassembling the gas cylinder, thus saving valuable rescue time.

4. Rescue Function:

During firefighting and rescue operations, when firefighters carrying air breathing apparatus enter a disaster environment and find victims, allowing the victims to breathe safe air greatly increases their chances of survival. However, since firefighters also need the air breathing apparatus for their own breathing, a regular positive pressure air breathing apparatus cannot supply air for two people simultaneously. News reports have frequently covered instances where firefighters provided their air breathing apparatus to victims, resulting in harm to themselves. Therefore, the air breathing apparatus has developed a rescue interface function, allowing one air breathing apparatus to supply air for two people simultaneously, thus solving the dilemma of whether rescuers should save themselves or others.