The document discusses trends in Singapore's air quality from 1993 to 2011, noting that air quality has improved significantly over that period. It also compares Singapore's air quality to other Asian and European/US cities. Additionally, it outlines Singapore's targets for reducing various air pollutants by 2020 and long term, and provides roadmaps for achieving the targets through measures related to vehicles and industries. Finally, it mentions enhancements to air quality reporting such as continuing to report the Pollutant Standards Index while also reporting daily PM2.5 levels.

1. Trends in Air Quality
• Our air quality has been improving
- Air quality in ‘Good’ range 96% of the time in 2011 compared
to 82% 10 years ago
AIR QUALITY IN TERMS OF PSI
( 1993 TO 2011 )
100
93 88 88 95 96
83 85 91 93 96
82
80 70 70
68
% of Days
64 65
61
60 4946 4948
39
40 32 36 35
30 30
17 18
20 12 12 14
7 5 4 9 7 4
0
93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11
Good Moderate Unhealthy

2. Trends in Air Quality
PM10 (Annual Mean)
80 Transboundary haze with
Unhealthy air quality days Transboundary haze with
Unhealthy air quality
µg/m3
60
days
40
20
0
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
PM2.5 (Annual Mean)
45 Euro IV Emission
Ultra Low Standards for
Sulphur Diesel Vehicles
35 Diesel from Oct 2006
(<0.005% S)
µg/m3
from Dec
25 2005
15
5
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

3. Trends in Air Quality
Sulphur Dioxide (Annual Mean)
50
40 Limit S content n Ultra Low
Natural gas for power Sulphur Diesel
fuel oil to 1% from generation
30 Dec 2005. (<0.005% S)
from Dec 2005
20
10
0
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
50
Ozone (Annual Mean)
40
µg/m3
30
20
10
0
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

4. Trends in Air Quality
Carbon Monoxide (Annual Mean)
10
8
6
mg/m3
4
2
0
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
Nitrogen Dioxide (Annual Mean)
50
40
µg/m3
30
20
10
0
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

5. Air Quality Benchmarked Against Asian Cities - Asian Green City Index
The Asian Green City Index, a 2011 research project by the Economist Intelligence
Unit, sponsored by Siemens, assessed the environmental performance of 22 Asian cities
across 8 criteria (Energy and CO2, Land use and
Buildings, Transport, Waste, Water, Sanitation, Air Quality, and Environmental Governance).
The chart compares the air quality data presented in the report.

6. Air Quality Benchmarked Against European and US Cities
80
70 SO2 NO2 PM10 PM2.5
60
Annual Average
50
40
30
20
10
0
Los Angeles (2011) Washington DC (2011)
Compiled by NEA from various published sources

7. 2 Air Pollution and Control Strategies

8. Air Pollution and Control Strategies
Domestic sources of air pollution
• Motor vehicles e.g. diesel vehicles account for about 50% of PM2.5
• Industries e.g. refineries & power stations account for more than 80% of SO2
Transboundary sources
• Smoke haze from land and forest fires in the region
Air pollution management & control strategies
• Integrated urban & industrial planning
• Development control
• Legislation, enforcement programme and monitoring
Pollutants of concern
• SO2 and PM2.5 are of concern
• NO2 and CO meet WHO AQGs. PM10 and ozone are marginally above WHO AQG

9. 3 Air Quality Targets for Singapore

10. 2020 Air Quality Targets for Singapore
Pollutant Singapore Targets Long Term Targets
By 2020
Sulphur dioxide (SO2) 24-hour mean : 50 µg/m3 24-hour mean : 20 µg/m3
(WHO Interim Target) (WHO Final)
Annual mean : 15 µg/m3
(Sustainable Singapore Blueprint)
PM2.5 Annual mean: 12 µg/m3 Annual mean: 10 µg/m3
(Sustainable Singapore Blueprint) 24-hour mean: 25 µg/m3
24-hour mean: 37.5 µg/m3 (WHO Final)
(WHO Interim Target)
PM10 Annual mean: 20 µg/m3
24-hour mean: 50 µg/m3
(WHO Final)
Ozone 8-hour mean: 100 µg/m3
(WHO Final)
Nitrogen dioxide (NO2) Annual mean: 40 µg/m3
1-hour mean: 200 µg/m3
(WHO Final)
Carbon monoxide (CO) 8-hour mean: 10 mg/m3
1-hour mean: 30 mg/m3
(WHO Final)

11. 3 Roadmap to Achieve Targets

12. Roadmap to Achieve 2020 Targets – Abatement Measures for Vehicles
1 Apr 2014
Emission
1 Jan 2014
standards for
Emission new petrol
standards for vehicles to be
1 Oct 2013 new diesel tightened from
Cleaner petrol for vehicles to be Euro II to Euro
motor vehicles tightened from IV
with sulphur Euro IV to Euro V
1 Jul 2013 content lower
Near sulphur- than 0.005%
free diesel
(0.001% S)
1 July 2012
Min emission stds (US Tier 2/Japan Tier
1/EU Stage II) for off-road diesel engines New measures
imported for use
Measures announced
at earlier COS

13. Roadmap to Achieve 2020 Targets – Abatement Measures for Industries
Reduce SO2 emissions from refineries
• Cleaner fuels such as natural gas and lower sulphur fuel oil
• Improve sulphur recovery processes
• Adopt cost effective measures and practices to further reduce emissions eg.
SO2 scrubbing system
Reduce SO2 emissions from power stations
•Currently, gencos use mainly natural gas (NG) and some fuel oil for
power generation
• Gencos will increase use of NG and lower sulphur fuel oil

14. 4 Enhancements to Air Quality
Reporting

15. Enhancements to Air Quality Reporting
Retain Pollutant Standards Index (PSI)
Report PM2.5 levels daily
• As an internationally harmonised protocol for reporting air quality
index is not available, countries adopt different index systems
• Most index systems are based on SO2, PM10, ozone, CO and
NO2. Only the US, Canada, UK and New South Wales/Australia
include PM2.5 in their Index
• Advisory Committee reviewed PSI adopted by NEA and has
recommended retaining PSI as it is backed by health studies and
is still relevant
• Countries in the region use indices similar to PSI. They do not
include PM2.5 in their index
• NEA will report PM2.5 and issue health advisories by region

16. Enhancements to Air Quality Reporting
Existing Enhancements
• PSI reported at 4pm by 5 regions • PSI and PM2.5 levels by 5 regions 3
(North, South, East, West & Central) times a day at 8am, 12noon & 4pm
• Health advisory issued for the whole • Health advisories will be issued by
of Singapore (not by region) region
• Hourly updates of 3-h PSI during • Continue with hourly updates of 3-h
smoke haze episodes PSI during smoke haze episodes
To commence on 24 Aug 2012

17. Example of Air Quality Information Posted on NEA Website
PSI Pollutant Concentration
Air Quality at 8 am on 17 Aug 2012
Region Health Advisory
24-hour PM2.5
PSI
Concentration (µg/m3)
None for the general population. Unusually sensitive people
North 44 34
should consider reducing prolonged or heavy exertion.
None for the general population. Unusually sensitive people
South 34 20
should consider reducing prolonged or heavy exertion.
None for the general population. Unusually sensitive people
East 42 26
should consider reducing prolonged or heavy exertion.
None for the general population. Unusually sensitive people
West 41 27
should consider reducing prolonged or heavy exertion.
None for the general population. Unusually sensitive people
Central 39 19
should consider reducing prolonged or heavy exertion.
Overall Singapore 34 - 44 19 - 34 -
*Sensitive groups : People with heart and lung diseases, older adults (ages 65 and above) and children.
Note: Air quality based on PSI is as follows:
PSI Value Air Quality Descriptor
0 – 50 Good
51 – 100 Moderate
101 – 200 Unhealthy
201 – 300 Very unhealthy
Above 300 Hazardous

18. Safeguard • Nurture • Cherish