Date ceased: Ceased in 2010-15 (source).
Official reason given: "Authorities are no longer required to report this data annually to the online spreadsheet. Please note that NI194 exists separately from local authority obligations under Local Air Quality Management, as prescribed under Article IV of the Environment Act 1995, and local authorities are still required to assess and report on air quality under the Review & Assessment criteria as set down in the Air Quality (England) Regulations 2000 and Policy and Technical Guidance 09." (source).
URL of example collection: Not known
Impact of cancellation (actions or decisions that are now hard or impossible to carry out a result of the cancellation): Not known
Do you know any more about why this dataset was discontinued, or its impact? Email anna@anna.ps