1月31日，在济南市英雄山路，市中区交警大队的交警戴口罩在一线执勤，当天济南市的空气质量为重度污染。近日，公安部发文表示，允许在空气严重污染时，各地对一线执勤民警根据情况采取调整勤务安排、改进执勤方式以及戴口罩等必要的防护措施。新华社记者 徐速绘 摄 On January 31,,In jinan city road hero,Leshan city traffic police brigade of the traffic police wearing a mask in a line of duty,The day of jinan city air quality for severe pollution.recently,The ministry of public security said outgoing mail,Allow in the air when serious pollution,On a line around the police on duty according to the circumstance adjustment service arrangement/Improve duty mode and wear a face mask and the necessary protective measures.Xinhua news agency reporter xu speed draw disturbing