NPI Reporting Explained: A Guide to Understanding Your Obligations

What is the NPI?

The NPI is a mandatory environmental reporting program that requires Australian facilities to report annually on emissions and waste transfers of listed substances. If your facility exceeds the NPI reporting thresholds, based on fuel usage or the quantity of NPI-listed substances handled, you are legally required to submit a report. The standard reporting period runs from 1 July to 30 June, with the submission deadline due by 30 September each year.

Who needs to report to NPI?

If your facility has the potential to release emissions or transfer waste in quantities that exceed the NPI reporting thresholds for any of the 93 substances listed in the National Environment Protection Measure (NEPM) NPI 1998, it’s important to assess your reporting obligations. You can do this via the NPI Guide.

If your facility meets Australian and New Zealand Standard Industrial Classification (ANZSIC) code, the flow chart below outlines the relevant category criteria.

Source: National Pollutant Inventory Guide - DCCEEW

The differing categories

The NPI is broken up into six different threshold categories and each of the 93 NPI substances are listed in one or more of the following categories:

Category 1 covers a broad range of NPI substances typically used for production with a use threshold of 10 tonnes or more per year.

Category 1a contains only Total Volatile Organic Compounds (TVOC) with a usage threshold of 25 tonnes or more per reporting year.

Category 1b contains only mercury and compounds or mercury with a usage threshold of 5 kg or more per reporting year.

Category 2a includes substances commonly produced through combustion or other thermal processes, such as when a facility burns 400 tonnes or more of fuel or waste over a reporting year, or burns at least 1 tonne within a single hour during that year.

Category 2b also contains substances that are products of combustion or other thermal processes, encompassing all Category 2a substances. It also covers metals and compounds emitted when fuels or waste are burnt. The

Category 2b reporting thresholds are as follows:

• Burning 2,000 tonnes or more of fuel or waste during the reporting year.
• Consuming 60,000 megawatt hours or more of electrical energy for purposes other than lighting, computing or motive power in the reporting year.
• Having a maximum potential power consumption of 20 megawatts or more for uses other than lighting or motive power during the reporting year.

Category 3 applies to thresholds that are based on the actual amount of total nitrogen and/or total phosphorus that are either emitted to water, transferred to a mandatory reporting transfer destination, or both. Reporting is required if emissions or transfers of total nitrogen and/or total phosphorus to a mandatory reporting destination, or both, meet or exceed 15 tonnes per year for total nitrogen or 3 tonnes per year for total phosphorus.

Estimating NPI emissions

Selecting the relevant Emission Estimation Technique (EET) manuals from the NPI website will allow for the identification of emissions associated with the industry sector of the reporting facility. These manuals will provide equations and emission factors to include both point and fugitive emissions and whether emissions are to air, land and/or water. Calculation tools are available within the NPI Online Reporting System (ORS) to assist with reporting. Alternatively, calculations can be performed independently using the NPI EET Manuals. For more complex assessment or support, a suitably qualified consultant can provide the necessary expertise and experience.

Estimating NPI Transfers

Transfers of Category 1, 1a, 1b, 2a, 2b and 3 substances within waste transferred, whether moved within the facility or off-site must be reported. The waste may be transferred to a mandatory or voluntary reporting destinations for the purpose of containment, destruction, energy recovery or treatment that leads to recycling, purification, remediation or immobilisation.

Avoiding common pitfalls in NPI data collection

A frequent challenge in preparing for NPI submissions is ensuring early and effective data quality assurance. Many facilities rely on multiple teams to gather data from diverse sources, which can lead to delays, inconsistencies, and confusion—especially around formatting and calculation requirements.

To streamline the reporting process and reduce risk, it's important to:

• Collect data consistently throughout the year.
• Review and validate data early, ensuring it aligns with NPI methodologies and reporting standards.
• Document data sources and conversion methods used in calculations to support transparency and enable year-on-year review.

As with any complex data process, having a second reviewer sign off on the data is a proven way to minimise errors and improve accuracy. At SLR, we’ve found that this level of support is highly valued by clients navigating the complexities of mandatory climate reporting.

Finalising NPI data and using the Online Reporting System (ORS)

Using the NPI ORS should be done once the facility emissions have been estimated. Data sets must be formatted to ensure they are easily auditable and take into consideration:

• Substance quantities
• Emission sources
• Estimation methods used
• Waste transfer destinations
• Data sources
• Calculation methods
• Assumptions and conversions

This can be a confusing experience, and a suitably qualified consultant can remove this stress for you.

Other reporting obligations

It is worth noting that if you trigger the reporting requirements for NPI, you should also consider if your organisation triggers any obligations under the Australian Sustainability Reporting Standards (ASRS) and National Greenhouse and Energy Reporting (NGER).

How we can help

If you require assistance managing your reporting obligations, from assessing reporting thresholds through to submitting your data, our team of experienced specialists can help guide you through the process.

To speak with one of our specialists, contact us today.

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Sources:

http://www.npi.gov.au/reporting/industry-reporting-materials/anzsic-code-list

NPI Guide - Version 6.1 September 2015

Emission Estimation Technique Manuals - DCCEEW