Amid China's perennial fight against smog, a group of special experts has been tasked with identifying air pollution - with their noses.
At the environment monitoring center in Shijiazhuang, in North China's Hebei Province, a group of pollution sniffers has been trained to identify air pollution by smelling it, as CGTN's Ning Hong reports. The sample air is collected near polluted locations by using vacuum bottles, and then diluted and siphoned into air bags.
It doesn't require a keen sense of smell to be a sniffer, but the experts must be officially licensed by local authorities. Wang Haiying, a senior pollution sniffer says that while various machines and detectors can be used to analyze pollution, the human nose still represents a quick and accurate barometer.
The results are then calculated and a conclusion is submitted to the city authority. While the nature of their role means these sniffers are often exposed to polluted air from unknown sources, Wang says the danger is not too serious.
To ensure accurate results, many sniffers choose not to use make up or eat any spicy food that may affect their sense of smell. But the sacrifice appears to be worth it for this hardy group of pollution sniffers.