Outside the temperature is 39 degree Celsius. But four police dogs are on duty sniffing for hidden dangers at a long-distance bus station in Shanghai, where there are about 30,000 daily passengers and almost 50,000 visitors each day. The police dogs check 2,500 suitcases and bags in the waiting hall and boarding areas every day. If there is anything unusual, they will give a warning to the police.

Their noses are 1,000 times more sensitive than that of human being. Dogs are born with thick skin and lack sweat glands. Therefore, they need lots of attention when working in hot weather. Every 15 minutes the police dogs are given water to drink and are wetted with a towel and ice. After a whole day’s work, their handlers will give them a bath as a reward, Zhang Jun, the handler of explosive detection police dogs told thepaper.cn.