What’s Actually Converging

California’s air emissions reporting is administered through dozens of regional Air Quality Management Districts, with statewide direction from the California Air Resources Board (CARB). Historically, reporting has been fragmented: different air districts maintained different notification lists, thresholds, and lookup processes, and criteria pollutant data and AB 2588 toxics data ran on separate tracks.

CARB’s CTR regulation, effective January 1, 2020 and amended effective January 1, 2022, is changing that. CTR establishes a standardized statewide framework for annual reporting of criteria pollutant and toxic air contaminant emissions. The regulation is being phased in over several years by facility class and the type of permitted process a facility operates. CTR applicability keys off permitted emissions and the process sector, not a facility’s Standard Industrial Classification (SIC) code. It does not merge the existing programs into one filing. It standardizes and broadens what gets reported, and several districts collect CTR data through their existing AER process, so the programs increasingly draw on the same underlying data even though AER, AB 2588, and CTR each keep their own legal authority and applicability rules.

Who Gets Pulled In

Facilities most likely to be affected by the broader reporting net:

• Paint and coating operations using materials that contain Toxic Air Contaminants (TACs)
• Plating and metal finishing shops with heated tanks (cadmium, nickel, hex chrome, lead)
• Combustion equipment operators: boilers, ovens, furnaces, large stationary engines
• Surface coating, printing, and solvent cleaning operations above district thresholds
• Aerospace manufacturing, electronics fabrication, semiconductor operations
• Any facility holding a permit from BAAQMD, SCAQMD, SJVAPCD, or the Sacramento air district

One thing worth being direct about: not appearing on an air district’s published notification list does not mean you’re exempt. As reporting broadens under CTR and district rules, a facility that has never received a notification letter may still be required to report based on the materials it uses or the equipment it operates.

A Timeline of What’s Changing

When the broader reporting actually lands: CTR took effect January 1, 2020 and was amended effective January 1, 2022. Facilities that have reported all along (larger greenhouse gas (GHG), criteria, and elevated-toxics sites) continued through their districts’ existing process. The wider net catches facilities newly pulled in under CTR’s added-applicability provisions, and for them annual reporting phases in by district group and the permitted-process sector involved: it begins with the 2026 data year (filed in 2027) for the earlier district group and the 2028 data year (filed in 2029) for the later group. What pulls a facility in is its permitted emissions and the processes it runs, not its SIC code, so the practical question is which of your permitted processes are in scope and in which year.

For a side-by-side comparison of how AER, AB 2588, and CTR (the California Air Resources Board’s Criteria and Toxics Reporting) actually differ as reporting programs, see our AER vs AB 2588 vs CTR guide. For AB 2588 specifically, see our AB 2588 Air Toxics Hot Spots reporting page.

Why Most Facilities Don’t Know This Is Coming

When we walk a facility for the first time, the AER is rarely on the client’s radar. The most common response when we ask is, “I’ve never heard of that.” A few patterns we see repeatedly:

• A facility checks a district’s published notification list, doesn’t see their name, and assumes they’re exempt. As CTR reporting phases in, that assumption is increasingly unsafe.
• A facility files every year because someone set it up years ago, but no one inside the company can describe what the report covers, whether new equipment has been added since, or whether the chemicals in use today are still the same chemicals on file.
• A facility changed ownership. The prior consultant stopped showing up. The AER quietly fell off the calendar. The district’s annual letter goes to an address that no longer exists.

The most common discovery point isn’t a regulator. It’s a site visit, where we cross-check the district’s notification list against the chemicals in use and the equipment on the floor, and identify a filing obligation the client didn’t know existed.

What to Do Now (Before the Filing Season)

Annual emissions reports cover the prior calendar year, January through December. Deadlines are set by each district and are not uniform statewide; SCAQMD’s Data Year 2025 reports and fees, for example, are due May 1, 2026, so confirm your district’s date. The first year a facility files is more work than subsequent years because the emission sources have to be inventoried from scratch and the calculation methodology has to be established.

Practical steps to take now:

Where CDMS Fits

We have prepared annual emissions reports for California facilities across BAAQMD, SCAQMD, SJVAPCD, and the Sacramento air district for decades. Our team works directly from each district’s calculation tools and report formats. We gather usage data from your records, calculate emissions for each source, apply waste shipment credits where they apply, and file through the district’s reporting portal.

If you’ve never filed, we start with an applicability review to confirm whether CTR or your district’s rules actually pull you in. If they do, we handle the filing end to end. If they don’t, we document why, so you have something on file if the district later asks. We won’t bill you for a report you don’t need.

For facilities already under our ongoing compliance management, the AER fits inside the annual calendar so it doesn’t get lost when staff turn over or priorities shift. Read more about keeping air permits and reports current.