Small inexpensive PM2.5 device developed in Japan

Scientists develop inexpensive mini PM 2.5 measuring gadget

August 06, 2015

By AYAKO TSUKIDATE/ Staff Writer

Researchers at Nagoya University have teamed with Panasonic Corp. to develop a small low-cost device that can detect and measure levels of PM 2.5 fine particulate pollutants, which have been a scourge in the skies over China and Japan in recent years.

Unveiled Aug. 5, the device will cost several thousands of yen (tens of dollars) to produce. Panasonic plans to install the device on air cleaners to go on sale in September.

The device was developed by a team led by Yutaka Matsumi, a professor of environmental studies at the university’s Solar-Terrestrial Environment Laboratory.

"We will be able to detect and measure pollutants by installing the device in various locations in a city," Matsumi said. "We hope the devices will reveal the everyday things that are acting as a source of pollution and help people deal with the health effects."

Measuring just 5 by 5 centimeters, the gadget easily fits into the palm of a hand and can detect PM 2.5, or particles 2.5 micrometers in diameter and smaller.

The device is able to measure pollutants as accurately as more expensive PM 2.5 detectors commonly used by local governments, and at a fraction of the cost. It costs about 100 times less to produce than the conventional detectors.

The device uses a light-scattering method to measure particles by beaming light emitted from LEDs into the air. It then uses an algorithm to compare the degree of light being scattered and the characteristics of different pollutants to pinpoint the size of the particles and how much of them are airborne.

Previously, the same method was unable to provide accurate readings of the density of particles smaller than 0.7 micrometers. But the new mini machine can give accurate readings of sizes as small as 0.3 micrometers. This feat was achieved by designing the interior of the device in a way that enables light to be collected more efficiently.