NOx
Oxides of nitrogen (NOx) are emitted when burning fuels. These form toxic chemicals - such as nitrate particles, acid aerosols and NO2 - which can cause respiratory problems and contribute to the formation of acid rain and nutrient overloads.
Work was undertaken in 2005 to determine whether our NOx emissions were significant, based on potential community health or environmental impacts. We concluded that our NOx emissions do not significantly impact airshed quality because either:
- NOx emissions from our operations are not significant as a proportion of total NOx emissions in an airshed (when other contributors are included), or
- Where our operations were considered to be a significant contributor, airshed quality did not appear to be significantly impacted by NOx emissions (indicated by NOx levels being within regulatory limits).
How we minimise the health risks
We identify and try to minimise air pollutant emissions and their potential impacts by applying our Air Quality Control Standard which calls for assessment and prioritisation of emission sources and requires installation of emission controls to ensure protection of ambient air quality.
Our results
Our oxides of nitrogen emissions (NO and NO2) are expressed as equivalent nitrogen dioxide (NO2) emissions.
- During 2007, our worldwide NO2 emissions were 64.2 thousand tonnes a slight increase on the 62.9 thousand tonnes in 2006. Emissions from mobile sources accounted for 44.0 thousand tonnes and stationary sources accounted for the remaining 20.2 thousand tonnes.