Regional cities' scorecard for ozone NEPM 4-hour standard, based on analysis of air quality index values, 1998-2014

This assessment summary component has changed from 2011.

  • The assessment summary in 2011 was assessed for the years 1999-2008

The original 2011 summary, grade, trend and confidence levels have been replicated here to assist comparison of changes between reporting cycles.

Regional cities’ score card for ozone (four-hour) NEPM standard, based on analysis of air quality index values, 1999–2008
Ambient air quality
State and trends
OzoneCoarse particulate matter (PM10)Air toxics
Regional cities' scorecard for ozone NEPM 4-hour standard, based on analysis of air quality index values, 1998-2014
Component
Summary
Grade
Very poor Poor Fair Good Very good
Confidence
In Grade In Trend
Comparability
To previous years

New South Wales - Kembla Grange - ozone (4-hour average)

Average percentage frequency distribution: very good 89; good 11; fair 0; poor 0; very poor 0

Year(s): 
2016
5
Improving
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Comparable

New South Wales - Kembla Grange - ozone (4-hour average)

20162011
Ambient air quality
State and trends

Approach/Process

The approach is based on the characterisation of the air quality of an airshed using its worst performing NEPM compliance station (monitoring site) for ozone. For regional NSW, that was the Kembla Grange station.

For each year from 2009 to 2014, monitoring data from the selected station were converted into air quality index values (AQI), which express the measured concentration as a percentage of the standard. An AQI of 100 means that the pollutant is present in the air at the level of the standard. The AQIs were allocated to one of the five qualitative categories commonly used by Australian environment protection agencies to report air quality (very good 0–33, good 34–66, fair 67–99, poor 100–149, and very poor 150+).

The yearly percentage distributions were then used as the basis for assigning an overall AQI for the pollutant at each station using the criteria set out in Table A. The assessment was compared with that given in SoE 2011 to assess the trend. Note that a percentage of <1 means that there are values in a particular category, albeit at a very low count, whereas a percentage of 0 means there are no values present in a category.

Table A Criteria for assigning overall AQI-based qualitative categories

 

Annual distribution of AQI values

Overall category

Very good (%)

Good (%)

Fair (%)

Poor (%)

Very poor (%)

Very good

>50

>20

<10

<10

<5

Good

>20

>30

<20

<20

<10

Fair

<10

<20

>30

>20

<10

Poor

<10

<20

<20

>30

>20

Very poor

<5

<10

<10

>20

>50

Supplementary rules for assessing overall AQI

  • If the percentage very good is greater than 45 and is also greater than the percentage good, the assessment grade is very good.
  • If the percentage good is greater than 75, the percentage very good can be as low as zero and the assessment grade is good.
  • If the assessment grade has stayed the same between 2011 and 2016 reports but the frequency of percentages within the grade has increased, the trend is set to ‘improving’ to reflect the increase.

 

Data/Information sources

Data used in assessment: Ozone concentrations (4-hour averages) from Kembla Grange in regional New South Wales

Quality of data used in assessment: High

 

Data custodian: New South Wales Environment Protection Authority

 

 

Comments

Nil.

Topics

Average percentage frequency distribution: very good 35; good 62; fair 2; poor 1; very poor 0

Year(s): 
2011
4
Stable
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Not assessed

Topics

Victoria – Moe/Traralgon - ozone (4-hour average)

This assessment summary component has changed from 2011.

  • Traralgon was not previously included in the 2011 assessment

The original 2011 summary, grade, trend and confidence levels have been replicated here to assist comparison of changes between reporting cycles.

Victoria—Moe

Average percentage frequency distribution: very good 99; good 1; fair 0; poor 0; very poor 0

Year(s): 
2016
5
Improving
Confidence (in grade): 
Somewhat adequate
Confidence (in trend): 
Somewhat adequate
Comparability (to previous reports): 
Comparable

Victoria – Moe/Traralgon - ozone (4-hour average)

20162011
Ambient air quality
State and trends

Approach/Process

The approach is based on the characterisation of the air quality of an airshed using its worst performing NEPM compliance station (monitoring site) for ozone. For regional Victoria, this was the Moe/Traralgon stations (the Moe site was closed in Q4 of 2009).

For each year from 2009 to 2014, monitoring data from the selected station were converted into air quality index values (AQI), which express the measured concentration as a percentage of the standard. An AQI of 100 means that the pollutant is present in the air at the level of the standard. The AQIs were allocated to one of the five qualitative categories commonly used by Australian environment protection agencies to report air quality (very good 0–33, good 34–66, fair 67–99, poor 100–149, and very poor 150+).

The yearly percentage distributions were then used as the basis for assigning an overall AQI for the pollutant at each station using the criteria set out in Table A. The assessment was compared with that given in SoE 2011 to assess the trend. Note that a percentage of <1 means that there are values in a particular category, albeit at a very low count, whereas a percentage of 0 means there are no values present in a category.

Table A Criteria for assigning overall AQI-based qualitative categories

 

Annual distribution of AQI values

Overall category

Very good (%)

Good (%)

Fair (%)

Poor (%)

Very poor (%)

Very good

>50

>20

<10

<10

<5

Good

>20

>30

<20

<20

<10

Fair

<10

<20

>30

>20

<10

Poor

<10

<20

<20

>30

>20

Very poor

<5

<10

<10

>20

>50

Supplementary rules for assessing overall AQI

  • If the percentage very good is greater than 45 and is also greater than the percentage good, the assessment grade is very good.
  • If the percentage good is greater than 75, the percentage very good can be as low as zero and the assessment grade is good.
  • If the assessment grade has stayed the same between 2011 and 2016 reports but the frequency of percentages within the grade has increased, the trend is set to ‘improving’ to reflect the increase.

 

Data/Information sources

Data used in assessment: Ozone concentrations (four-hour averages) from Moe/Traralgon in regional Victoria. Note that the Moe site was closed in the last quarter of 2009.

Quality of data used in assessment: High

 

Data custodian: Environment Protection Authority Victoria

 

 

Comments

Nil.

Topics

Average percentage frequency distribution: very good 68; good 31; fair 1; poor 0; very poor 0

Year(s): 
2011
5
Unclear
Confidence (in grade): 
Adequate
Confidence (in trend): 
Limited
Comparability (to previous reports): 
Not assessed

Topics

This period includes the 2014 Hazelwood mine fire, which affected the Victorian towns of Moe and Traralgon. The NEPM site at Moe was discontinued in quarter 4 of 2009.

Assessment Summary Key

Grades

Very good

Air quality is considered very good, and air pollution poses little or no risk

Good

Air quality is considered good, and air pollution poses little or no risk

Fair

Air quality is acceptable. However, there may be a health concerns for very sensitive people

Poor

Air quality is unhealthy for sensitive groups. The general population is not likely to be affected in this range

Very poor

Air quality is unhealthy, and everyone may begin to experience health effects. People from sensitive groups
may experience more serious health effects

Recent Trends

  • Improving

  • Stable

  • Deteriorating

  • Unclear

Confidence

  • Adequate: Adequate high-quality evidence and high level of consensus

  • Somewhat adequate: Adequate high-quality evidence or high level of consensus

  • Limited: Limited evidence or limited consensus

  • Very limited: Limited evidence and limited consensus

  • Low: Evidence and consensus too low to make an assessment

Comparability

  • Comparable: Grade and trend are comparable to the previous assessment

  • Somewhat comparable: Grade and trend are somewhat comparable to the previous assessment

  • Not comparable: Grade and trend are not comparable to the previous assessment

  • Not previously assessed

Keywood MD, Emmerson KM, Hibberd MF (2016). Ambient air quality: Regional cities' scorecard for ozone NEPM 4-hour standard, based on analysis of air quality index values, 1998-2014 . In: Australia state of the environment 2016, Australian Government Department of the Environment and Energy, Canberra, https://soe.environment.gov.au/assessment-summary/ambient-air-quality/regional-cities-scorecard-ozone-nepm-4-hour-standard-based, DOI 10.4226/94/58b65c70bc372