Guideline for Air Quality Standards in the NWT - 2014 Summary Ambient air quality standards are used to determine the acceptability of emissions from proposed and existing developments and for reporting on the state of air quality in the NWT. 2014 Current Resource Guideline for Air Quality Standards in the NWT - 2014 PDF • 88.54KB • Issued January 31, 2014 Download Guideline for Air Quality Standards in the NWT - 2014