Air quality surveys
<DocumentSelector><Library>Published Reports</Library><Group></Group><Subgroup></Subgroup><ContentType></ContentType><Subject>Air Quality</Subject><OrderBy>Title</OrderBy><Documents>27,209,210,68</Documents></DocumentSelector>
Sigma Group (Christchurch) Limited, 1997: 1997 Air Quality Survey. Report prepared for the Canterbury Regional Council, July 1997.
Sigma Group (Christchurch) Limited, 1998a: 1998 Air Quality Survey: Analysis of the Main Messages of the Air Pollution and Winter Smog Campaign. A report prepared for the Canterbury Regional Council, July 1998.
Johnston, J., Gurnsey, P., 2000: Ambient Air Quality Complaints 1999: A technical background report. Canterbury Regional Council Report No. U00/01, January 2000.
Please contact customer services for a printed copy of the reports listed above.