PRTR explained for industrial sites and Scottish reporting
PRTR means pollutant release and transfer register. Learn which Scottish sites report to SEPA, what thresholds mean and how to read facility data.
PRTR means pollutant release and transfer register: a public inventory of reported pollutant releases and transfers from covered facilities. Scotland's register is the Scottish Pollutant Release Inventory (SPRI), run by SEPA, which publishes annual releases and off-site transfers. SEPA's overview explains its scope.
For a Scottish operator, the starting point is the site's activity, capacity and reporting notice. This guide focuses on those Scottish reporting duties and how to read the published data. A reported release does not by itself establish a licence breach: SEPA separates reporting thresholds from licence limits in its SPRI glossary.
Which PRTR do you need?
PRTR is a general term, not one worldwide reporting system. The register names below identify different scopes and reporting requirements. Do not use a threshold from one register to decide whether another requires a return.
| Register | Where it fits | Official starting point |
|---|---|---|
| SPRI | Scottish industrial releases and off-site waste and wastewater transfers | SEPA overview |
| UK PRTR | UK register receiving a subset of SPRI data | SEPA methodology |
| European Pollutant Release and Transfer Register, or E-PRTR | EU framework transitioning to the Industrial Emissions Portal framework | European Commission |
| Toxics Release Inventory, or TRI | US reporting on toxic chemical releases and pollution-prevention activities | US EPA |
| National Pollutant Release Inventory, or NPRI | Canada's public inventory of releases, disposals and transfers | Government of Canada |
For US facilities, EPA describes reporting for listed chemicals manufactured, processed or otherwise used above applicable thresholds. Its facility reporting page gives a 1 July deadline for the previous calendar year.
The Canadian National Pollutant Release Inventory has its own reporting requirements under the Canadian Environmental Protection Act. Its public search supports reporting-year and company or facility-name searches, including NPRI IDs. Neither system determines a Scottish site's obligations.
Which Scottish sites must report to SEPA?
SEPA's current SPRI guidance describes 67 activities across 10 major sectors, subject to activity and capacity criteria. It says organisations served with a Regulation 37(1) Notice under the Environmental Authorisations (Scotland) Regulations 2018 must complete annual returns.
Read the activity description before selecting a capacity figure. SEPA's activity table lists independently operated industrial wastewater treatment serving listed activities. It shows 10,000 m³/day, with 2,000 m³/day for Scotland. Using only the larger figure would miss the Scottish distinction.
The same table shows "None" in the refinery capacity field. That means no numerical capacity threshold is shown for that activity. It does not mean every business falls within SPRI. Check the listed activity and the site's notice together.
A shutdown does not automatically remove the reporting requirement. SEPA says a site that has not operated may still need a return. A site closing during the reporting year reports for its operational period. Use the current guidance rather than assuming that no production means no paperwork.
What PRTR thresholds actually mean
There is no single SPRI emissions threshold that answers every reporting question. Start with activity and capacity criteria to assess coverage, then check the thresholds for each pollutant. Published statistical totals and the UK PRTR subset do not include every SPRI record. SEPA's methodology explains these distinctions.
That methodology uses ART for "Above Reporting Threshold" and BRT for "Below Reporting Threshold". Its published total emissions and facility counts use ART submissions only. BRT does not mean zero emissions, so an ART-only total should not be read as a count of every release.
For a current return, use the reporting-year instructions linked from SEPA's overview. Do not infer from a BRT classification alone that you can omit an emissions value. The classification and the required entry are separate questions.
An ART entry means a reporting threshold was exceeded, not that a licence limit was breached. SEPA makes that distinction in its glossary. Its 2024 methodology also says SPRI data is not used to assess regulatory compliance. Do not treat an ART entry as a finding that a site broke the law.
Releases and transfers are different records
SPRI covers specified pollutant releases to air and water, alongside off-site transfers of waste and wastewater. Moving waste off-site for management is not the same event as releasing a pollutant directly into the environment. The UK PRTR dataset guidance separately identifies waste transfers and transfers of pollutants in wastewater.
Keep those categories separate when reading facility data. A waste-transfer amount answers a different question from an air-release amount. Check the record's category before describing what a facility released or transferred.
The 2024 methodology gives off-site waste-transfer thresholds of 2 tonnes for hazardous waste and 2,000 tonnes for non-hazardous waste. Those figures describe that published methodology. For a current return, check the reporting-year schedule rather than treating historical figures as a current compliance checklist.
How to find a site's reported releases
Start with the official Scottish Pollutant Release Inventory 2024 publication. It links to the public SPRI application and provides access to bulk downloads, including facility-level data. It also describes summaries by industry sector for pollutants and waste transfers.
Use the facility-level data for the site and reporting year you need. Keep releases separate from waste and wastewater transfers. Check ART and BRT classifications before comparing records with the published totals, because those totals use ART submissions only. The methodology explains that statistical coverage.
A missing result is not proof of zero emissions. SPRI has defined activity coverage and reporting classifications, rather than covering every Scottish emission source. Use the publication and its supporting methodology to understand what the data includes before drawing conclusions about an absent facility.
Scottish and UK results can also differ. SEPA says SPRI supplies a subset to the UK PRTR. SPRI includes information useful at Scottish scale, including radioactive substances and lower thresholds for some activities and pollutants. The methodology explains why the two datasets are not interchangeable.
Reporting deadlines are not publication dates
SEPA's current overview gives 28 February as the annual submission deadline and says returns are submitted by email. The dated methodology describes returns for the previous calendar year, with that deadline applying to most facilities. Check the site's notice and reporting-year instructions for its return.
Publication follows a separate timetable. As checked on 6 November 2026, SEPA's publications index schedules 2025 data for 17 November 2026. The latest completed release listed is 2024, published on 30 September 2025. A scheduled release is not yet available data.
For UK-wide downloads, Defra's guidance says the UK PRTR is moving to a new system. Industrial emissions datasets are available in CSV and XML in the meantime.
E-PRTR and the EU portal transition
If you searched for "European pollutant emission register", the E-PRTR framework and its successor are the relevant EU starting points. Regulation (EU) 2024/1244 establishes the Industrial Emissions Portal framework. It applies from 1 January 2028 and repeals Regulation (EC) No 166/2006 from that date. The regulation's transitional provision preserves the older rules for reporting for 2026.
The European Commission says the first data under the new law will describe 2027 and appear in 2028. The new framework adds information on energy, water and key raw-material consumption. An accessible portal does not mean the new law already applies, or that it automatically changes Scottish reporting duties.
RegAffairs AI has a public answer on PRTR reporting for Scottish industrial sites. For facility-level Scottish data, the official SPRI publication provides the application link and bulk-download route.