About the NPI
Get answers to the most commonly asked questions about the NPI.
The National Pollutant Inventory (NPI) is a publicly accessible database containing information on the types and amounts of pollutants being emitted to the Australian environment.
Information in the database is supplied by state and territory environment agencies who receive the information from facilities in their jurisdictions. Industry information on the database is updated annually.
The purpose of the inventory is to help assess the nature of pollution in Australia by drawing together information about pollutants being released into the environment. The NPI identifies the sources of emissions and whether they are emitted to air, water or land.
The NPI helps everyone to keep an eye on pollution - it's your right to know.
The NPI can give you information on the types and amounts of pollutants being emitted across Australia or in specific locations. Using the NPI online, you can find out about pollutant emissions in your local area and learn more about the environmental impact of local industry and everyday activities.
The NPI contains data on 90 substances that are emitted to the environment - our air, water or land. The substances included in the NPI have been identified as important because of their possible health and environmental effects. More about NPI substances
Small levels of emissions may be significant. For example, small emissions of highly toxic substances can be of more concern than large emissions of less toxic substances. The specific characteristic of a substance and the circumstances of exposure must also be considered when assessing the human health and the environmental risks. More background information on NPI substances.
No. Adding together emissions of different substances does not provide a measure of total pollution. This is because NPI substances have differing properties and toxicities. It is like comparing 'apples' and 'oranges' - both are fruit, but they are quite different.
The NPI provides data on emissions only. Pollution control is the responsibility of states and territories. To report pollution incidents contact your relevant state or territory environment agency. Whether emissions of a substance cause pollution depends on the amount of substance emitted, where it is emitted, the weather conditions at the time and the topography of the land.
For NPI reporting purposes emissions are defined as the release of an NPI substance to the environment whether in pure form or contained in other matter and/or in solid, liquid or gaseous form. It includes the release of substances to the environment from landfill, sewage treatment plants and tailings dams. All emissions are separated into emissions to air, land and water.
Industries as diverse as sugar milling, soft drink making, mining, hospitals and brick manufacturing, report to the NPI. A full list of industries can be found on the NPI web site. Industry facilities which trip an NPI substance threshold are required to report to the NPI. Thresholds are outlined in the NPI guide. More about reporting to the NPI, list of industry sectors and the NPI guide.
Each industry has an Emission Estimation Technique (EET) Manual which contains detailed information on estimating emissions. Estimation techniques include direct measurement, mass balance engineering equations and emission factors. Alternative EETs may be used providing they have state or territory environment agency approval. Manuals are available online or by calling your local NPI officer. Facilities are required to report emissions above established thresholds to their state or territory environment agency once a year. More about estimating emissions and NPI contacts.
Measurement of emissions can be prohibitively expensive and difficult for many facility occupiers. Facilities that monitor specific pollutants may report these measurements as their emission estimates.
Emission levels may vary because more facilities are reporting their emissions, or there are changes in factory levels of production, improved environmental performance, changes to the process, installation of pollution control equipment such as fabric filters, and updated estimation techniques.
The accuracy of the emission estimations data depends on the emission estimation technique used, availability of local data, site-specific conditions and available resources. Facilities are expected to use the best available emissions estimation methodology.
No. There are no reporting exemptions for facilities that have an NPI industry emission estimation technique manual and trip the NPI thresholds. The NPI National Environment Protection Measure (NEPM) specifically excludes the following types of facilities from reporting to the NPI:
More about the National Environment Protection Measure (NEPM)
If a facility uses more than 10 tonnes of selected NPI substances, or consumes more than a specified amount of energy, or emits more than a certain amount of total nitrogen or total phosphorus to water, then it is required to estimate and report its emissions. Only those facilities that exceed certain thresholds appear on the NPI. More about reporting thresholds
Relevant state or territory environment agencies are responsible for enforcing NPI requirements. These agencies may take action if a facility occupier does not provide information or provides false or misleading information to the nominated agency. Enforcement provisions vary between the states and territories consistent with other aspects of their environmental legislation. More about NPI enforcement can be obtained from your local state or territory environment agency.
An emission factor is used to estimate emissions to the environment. Emission factors are formulae that relate known emission characteristics to other variables that are easier or more economical to monitor than the pollutants themselves. For the NPI, emission factors generally relate the quantity of substances emitted from a source to the facility's production levels. Emission factors are obtained from US, European, and Australian sources. The NPI Guide contains more detailed information on reporting to the NPI. More about the NPI guide .
Fugitive and point source emissions are substances which escape to air from a source not associated with a specific process but from throughout the plant, such as leaks from equipment or dust blown from stockpiles. Many facilities report their stack and fugitive emissions separately. On the NPI database select the Facility and its Detailed Facility Emission Report to see if there are separate stack and fugitive emissions reports.
Diffuse emissions data reflects emissions from non-industrial activities such as transportation, domestic and commercial activities , and emissions from industry that are not reported because the relevant thresholds are not exceeded or the industry is excluded from reporting. Diffuse data reflects the total emissions from an airshed or catchment area.
No. Comparing diffuse data is likely to be misleading since state and territory environment agencies have used different methodologies to estimate the data. As the methodologies improve and quality and quantity of data on which the estimations are based become more robust, more meaningful comparisons of the data will be possible.
The accuracy of the data depends on the methodology that the state and territory environment agencies employed in the estimation as well as the quantity and accuracy of the data on which the estimations are based. All the states and territories use the best available methodologies. Diffuse emissions estimations manuals are available and the states and territories are using these to assist with their diffuse data estimations. More about diffuse emissions manuals
Diffuse data provides an indication of the emissions from non-reporting facility sources for the regions for which studies have been undertaken. Although reflecting the most up-to-date information, diffuse data may not be as current as NPI information for particular facilities, which is provided annually. For example, diffuse data may be from a study completed in 1998-99 and the facility data from 2004-05. This needs to be considered if you wish to study pollutant emissions from a specific region.