Air Filtration

Each time we breathe in, we expose ourselves to a range of airborne particles that can exacerbate allergies and asthma and cause respiratory infections.

To kill these harmful particles, researchers have constructed a new device called the soft x-ray electrostatic precipitator, which functions more efficiently than the standard air filters used in most hospitals, aircraft, and homes today, according to a study published in the journal Applied and Environmental Microbiology.

The device, known for short as SXC ESP, not only captures particles often missed by standard air filters, but inactivates them as well, said study co-author Pratim Biswas of Washington University in St. Louis.

It has a range of potential uses, including providing protection for people with respiratory illnesses or inhalation-induced allergies, shielding buildings from bio-terror attacks, filtering air in clean rooms used for semiconductor fabrication, removing ultrafine particles in power plants, and capturing diesel exhaust particulates, said Biswas in a press release.

According to the study, scientists used this technology to successfully protect mice from airborne pathogenic bacteria, viruses, ultrafine particles, and allergens. The SXC ESP works by giving the particles an electrical charge and then using an electrical field to trap and inactivate them.

Asthma By the Numbers

According to the Centers for Disease Control and Prevention, 18.9 million adults and 7.1 million children are living with asthma, “a chronic respiratory disease that can be triggered by inhalation exposure to diesel soot as well as allergens such as fungal spores, pollen, and pet dander."  According to the study, asthma was ranked the fifth-most costly health care expenditure in the U.S. in 2006, at $51.3 billion dollars.

“Considering that citizens of developed nations normally spend 87 percent of their time indoors, properly maintaining indoor air-quality is clearly an absolute necessity for the protection of public health,” the study authors wrote.

The standard filters used in today’s hospitals, aircraft, and cars are HEPA filters, which are capable of removing airborne particles larger than 0.3 micrometers with 99.97 percent efficiency. This level of efficiency is vital when it comes to hospital air handling systems that “service operating rooms where bone marrow transplant and medical device implant surgeries are performed,” the authors said.

However, the SXC ESP exceeds this standard of efficiency, and maintaining the quality of most HEPA filters can be quite costly, requiring additional energy consumption and regular filter replacement.

“Because of lower power requirements and reduced maintenance costs, electrostatic precipitation (ESP) has established itself as a feasible particulate control alternative,” the study authors wrote.

“Cost is not too high,” Biswa said, “--cheaper in the long run than HEPA filter systems.”

Cleaner Air Is on the Horizon

Consumers won’t have to wait long before soft X-ray enhanced electrostatic precipitation technology is incorporated in a variety of applications, said Biswas in an interview with Healthline. The possibilities seem endless.   

“A company, ACT, is working on commercializing it now,” he said.

According to Biswas, we can expect this new air filtration system to be integrated into diesel engine exhausts, indoor air conditioners, bio-hoods, refrigerators, residential HVAC systems, medical clean rooms, and even prisons.

This technology is ideal for indoor air quality improvement, and could provide a remedy for allergy sufferers at a low cost. It also comes in various shapes and sizes to fit your needs—“cylindrical, tubular or rectangular,” Biswas said.

Learn More: