Published on : Jul 17, 2015
According to a new study, air filters which are used to clean the air more efficiently, are involuntarily releasing more dangerous chemicals into the environment. The study at Concordia University in Canada has revealed that a certain category of air filter called photo catalytic oxidation (PCO) which is already present in the market, releases carcinogen such as formaldehyde. The researchers have mentioned that this is the first time that the air filter systems have been independently tested. Lexuan Zhong, a doctoral graduate at the university, along with Professor Fariborz Haghighat, has presented the findings of their testing of the PCO systems which filter air with the help of the ultraviolet light.
Haghighat, a professor with the Department of Building, Civil, and Environmental Engineering at the University mentioned that the results have shocked the researchers as some of the gases coming out of the PCO systems are more dangerous than the original gas. He further added that it is a challenge to fight the chemical contaminants as they are present in various perfume products, paint, treated wood, and carpets. He pointed out that at times the concentration of the gases inside the building is around ten times more than outside. Though there are regulations to limit percentage of chemicals in the air, there are fewer governing specific technologies. Haghighat said that if a company says a new technology is working, the public accepts it blindly even though it has not been tested by a standards organization which usually takes 10-15 years.
The researchers have said that apart from developing systems that filter the air without adding harmful by-products, energy consumption need to be reduced. The present mechanism employed in the PCO systems is not energy efficient.