How EPCRA Tier II reporting works
Tier II is the annual hazardous-chemical inventory report required by the Emergency Planning and Community Right-to-Know Act (EPCRA §312), administered by EPA through your state and local emergency-planning agencies. It is separate from your OSHA Hazard Communication program (29 CFR 1910.1200) — but it draws on the same chemical inventory and safety data sheets, so contractors usually build both from one list.
You owe a Tier II report for any calendar year in which a hazardous chemical was present at your facility at or above its reporting threshold at any one time. The threshold depends on what kind of chemical it is:
What counts as a “hazardous chemical”?
EPCRA borrows OSHA's definition: a hazardous chemical is anything for which your employer must keep a Safety Data Sheet under the OSHA Hazard Communication Standard (29 CFR 1910.1200(c)) — referenced by 40 CFR 370.10. In practice, if a product has an SDS, it is in scope for Tier II screening. A handful of items are excluded (food, drugs and cosmetics in retail packaging for the public, substances used by the general public the same way, and certain research-lab quantities), but for a construction or industrial site the working rule is simple: every SDS-bearing chemical gets screened against its threshold.
EPCRA §311 vs. §312: two separate duties
People conflate these, then miss a deadline. They are different filings off the same inventory:
- §311 — SDS / list submission (one-time, then on change). When a chemical first crosses its threshold you must give your SERC, LEPC, and fire department either the SDS or a list of your hazardous chemicals. You update it when a new chemical crosses threshold — it is not an annual filing.
- §312 — Tier II inventory (every year by March 1). The annual quantity-and-location report this screener checks (40 CFR 370.10). It is due every year you are at or above a threshold, covering the prior calendar year (40 CFR 370.45).
Both use the same thresholds below. This tool screens the §312 trigger; if a chemical is reportable here, you also have a §311 obligation for it.
2026 Tier II reporting thresholds
Thresholds under 40 CFR 370.10. These figures are unchanged for 2026 — EPA's November 17, 2025 direct-final rule was withdrawn on January 9, 2026, so the long-standing numbers remain in force.
| Chemical kind | Reporting threshold | Cite |
|---|---|---|
| Hazardous chemical (non-EHS, has an SDS) | 10,000 lb | 40 CFR 370.10(a) |
| Extremely Hazardous Substance (EHS) | Lower of 500 lb or the TPQ | 40 CFR Part 355, Appendix A (TPQ) |
| Retail gas-station gasoline (underground tanks) | 75,000 gal | 40 CFR 370.10(a)(2)(ii)-(iii) |
| Retail gas-station diesel (underground tanks) | 100,000 gal | 40 CFR 370.10(a)(2)(ii)-(iii) |
The amount that matters is the maximum present at any one time during the year, not an average. The retail-UST thresholds apply only to gasoline/diesel in tanks entirely underground at a retail station in compliance with 40 CFR Part 280; non-retail or above-ground fuel uses the normal 10,000-lb threshold.
The EHS trap: never assume a flat 500 lb
For an Extremely Hazardous Substance, the threshold is the lower of 500 lb or the substance's Threshold Planning Quantity (TPQ) (40 CFR Part 355, Appendix A (TPQ)). Because many EHS have a TPQ well below 500 lb, the TPQ usually governs — so a small drum can trip the threshold. Confirm the TPQ for your substance in 40 CFR Part 355 Appendix A. A few common ones:
| EHS | CAS | TPQ | Effective threshold |
|---|---|---|---|
| Chlorine | 7782-50-5 | 100 lb | 100 lb |
| Ammonia (anhydrous) | 7664-41-7 | 500 lb | 500 lb |
| Sulfuric acid | 7664-93-9 | 1,000 lb | 500 lb |
| Hydrogen fluoride / Hydrofluoric acid | 7664-39-3 | 100 lb | 100 lb |
| Formaldehyde | 50-00-0 | 500 lb | 500 lb |
Worked examples
1) 8,000 lb of acetone (non-EHS). Acetone has an SDS and is not on the EHS list, so its threshold is 10,000 lb. 8,000 lb is below 10,000 lb, so acetone alone does not trigger Tier II. If you also store 11,000 lb of paint thinner, that chemical is over threshold and the whole facility must file.
2) 150 lb of chlorine (EHS). Chlorine's TPQ is 100 lb, and the threshold is the lower of 500 lb or the TPQ — so 100 lb governs. 150 lb is at or above 100 lb, so chlorine is reportable even though it is far below the 10,000-lb non-EHS figure. This is the classic EHS trap.
3) 60,000 gal of gasoline in a station's underground tanks (retail UST). A retail gas station storing gasoline in tanks entirely underground uses the higher retail-UST threshold of 75,000 gal (40 CFR 370.10(a)(2)(ii)-(iii)). 60,000 gal is below 75,000 gal, so it is not reportable. The same 60,000 gal in an above-ground tank, or at a non-retail site, would instead be measured against the 10,000-lb non-EHS rule and would be reportable. Diesel uses 100,000 gal.
What to do if a chemical is reportable
- File the Tier II form by March 1 for the prior calendar year (40 CFR 370.45). Most states require electronic filing through Tier2 Submit or a state portal.
- Send it to all three recipients: State Emergency Response Commission (SERC); Local Emergency Planning Committee (LEPC); Local fire department with jurisdiction over the facility.
- Keep your inventory current. A maintained chemical inventory with peak quantities and SDSs is the source document for both Tier II and your OSHA HazCom program.
- Re-screen when quantities change. A one-time spike above the threshold during the year still creates a reporting obligation.
Frequently asked questions
Do I have to file Tier II for 8,000 lbs of a hazardous chemical?
No. For an ordinary OSHA-hazardous chemical that is not an Extremely Hazardous Substance, the EPCRA Tier II threshold is 10,000 pounds (40 CFR 370.10). At 8,000 lb you are below the threshold for that chemical, so it does not trigger Tier II by itself. If any other chemical on site reaches its own threshold, you would still have to report.
What is the Tier II reporting threshold?
Under 40 CFR 370.10, an OSHA-hazardous chemical that is not an Extremely Hazardous Substance (EHS) must be reported if you have 10,000 lb or more on site at any one time. For an EHS, the threshold is the LOWER of 500 lb or that substance's Threshold Planning Quantity (TPQ) from 40 CFR Part 355 Appendix A. Retail gas-station fuel in underground tanks uses higher thresholds: 75,000 gallons of gasoline or 100,000 gallons of diesel.
What is the threshold for an Extremely Hazardous Substance (EHS)?
The EHS threshold is the lower of 500 lb or the substance's Threshold Planning Quantity (TPQ). Because many EHS have a TPQ below 500 lb, you must look up the actual TPQ in 40 CFR Part 355 Appendix A — never assume a flat 500 lb. For example, chlorine has a TPQ of 100 lb, so 100 lb on site triggers reporting.
Does the threshold apply per chemical or to the whole facility?
Per chemical. You compare each hazardous chemical's maximum on-site amount against its own threshold. The facility's duty to file Tier II is triggered if ANY single chemical meets or exceeds its threshold — there is no facility-wide tonnage total. This screener checks one chemical at a time; add each chemical you store and watch whether any line comes back 'reportable'.
What amount do I measure — average or peak?
The maximum amount present at the facility at any one time during the calendar year (40 CFR 370.10). Use your peak inventory, not an average or year-end snapshot. Mixtures count by the weight of the hazardous component, and you may report the mixture as a whole or by component, whichever you choose consistently.
When is the Tier II report due and who gets it?
The annual Tier II form is due on or before March 1 each year, covering the prior calendar year (40 CFR 370.45). It is submitted to your State Emergency Response Commission (SERC), your Local Emergency Planning Committee (LEPC), and the local fire department with jurisdiction over your facility.
What is the difference between EPCRA §311 and §312?
They are two filings off the same chemical inventory. §311 is the SDS/list submission: when a chemical first reaches its threshold you provide the SDS (or a list of your hazardous chemicals) to the SERC, LEPC, and fire department, and update it only when a new chemical crosses threshold — it is not annual. §312 is the annual Tier II inventory report (40 CFR 370.10), due every year by March 1 for the prior calendar year. This screener checks the §312 trigger; a chemical that is reportable here also creates a §311 obligation.
What makes a chemical a 'hazardous chemical' for Tier II?
EPCRA uses OSHA's definition: 40 CFR 370.3 defines a hazardous chemical as one defined under 29 CFR 1910.1200(c), and 370.12 applies it to what you must report. As a working rule, if a product has an SDS it is in scope for Tier II screening. 40 CFR 370.3 excludes: (1) any food, food additive, color additive, drug or cosmetic regulated by the FDA; (2) a substance present as a solid in a manufactured item, to the extent exposure does not occur under normal conditions of use; (3) a substance used for personal, family or household purposes, or present in the same form and concentration as a product packaged for distribution and use by the general public; (4) a substance used in a research laboratory, hospital or other medical facility under the direct supervision of a technically qualified individual; and (5) a substance used in routine agricultural operations, or a fertilizer held for sale by a retailer to the ultimate customer. Most SDS-bearing chemicals on a worksite must still be screened.
Is Tier II an OSHA requirement?
No. Tier II is an EPA right-to-know requirement under EPCRA §312 (40 CFR Part 370), administered through your state and local emergency-planning agencies. It is separate from your OSHA Hazard Communication program (29 CFR 1910.1200), although both rely on the same chemical inventory and safety data sheets.
Did the 2026 thresholds change?
No. EPA published a direct-final rule on November 17, 2025 but withdrew it on January 9, 2026, so the long-standing numeric Tier II thresholds (10,000 lb non-EHS; lower of 500 lb or TPQ for EHS; 75,000/100,000 gal retail UST) remain in force for 2026.
Sources & verification
- https://www.ecfr.gov/current/title-40/chapter-I/subchapter-J/part-370/subpart-B/section-370.10
- https://www.ecfr.gov/current/title-40/chapter-I/subchapter-J/part-370/subpart-C/section-370.45
- https://www.ecfr.gov/current/title-40/chapter-I/subchapter-J/part-355/appendix-Appendix%20A%20to%20Part%20355
- https://www.epa.gov/epcra/tier-ii-forms-and-instructions
Thresholds verified 2026-06-23 against eCFR (40 CFR Parts 355 & 370) and EPA guidance. This screener is an estimate for planning only — it is not legal advice. Tier II is an EPA program, not OSHA; your state may impose additional fees, lower thresholds, or extra reporting.
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