AIR quality assessments by the Chinese Government don’t match those of the U.S. consulate in Shanghai because they use different standards, Shanghai environmental officials said Tuesday.

    The U.S. consulate Monday began publishing PM2.5 readings, which measure particulate matter of 2.5 microns or less in diameter.

    The PM2.5 reading was 152 at noon Tuesday, compared with 122 at the Pudong monitoring site and 155 at the Putuo site, two stations run by the Shanghai Environmental Monitoring Center.

    However, the U.S. consulate rated air quality as “very unhealthy” based on the calculated air quality index, while the assessment from the Shanghai center was “favorable.”

    “The divergence lies in the different bases for evaluation,” said Luo Hailin, deputy chief engineer at the Shanghai environmental protection bureau. “Our evaluation is based on the air pollution index, which looks at sulfur dioxide, PM10 and oxynitride, while their assessment is based on the air quality index, which focuses on PM2.5.”

    The difference comes from the evaluation standards adopted by the two countries, which are at different stages of economic development and environmental protection, experts said. The United States uses the standard for the third stage suggested by the World Health Organization, while China uses that of the first stage.

    “The monitor is an unofficial source for the health of the consulate community. Citywide analyses cannot be done on data from a single monitor,” read a notice on the consulate’s microblog Monday.

    (SD-Agencies)