Roadway air volume measuring method

The invention discloses a roadway air volume measuring method which comprises the following steps: arranging a sulfur hexafluoride quantitative control release device on the windward side of a roadway to be measured so as to release sulfur hexafluoride gas in a fixed release amount; arranging a sulfur hexafluoride concentration measuring device on the leeward side of the roadway to be measured, and measuring the sulfur hexafluoride concentration at a plurality of measuring points in the section of the roadway; comparing the sulfur hexafluoride concentration values at a plurality of measuring points in the section, and if the sulfur hexafluoride concentration values at the measuring points in the section are equal, indicating that the sulfur hexafluoride is uniformly mixed with the roadway airflow; if the sulfur hexafluoride concentration values at all the measuring points in the section are not equal, continuously measuring the sulfur hexafluoride concentration values at all the measuring points in the next s