Tier II reporting thresholds, with worked examples

Published by Vertexium Environmental Solutions LLC · Last updated October 9, 2026

A chemical is reportable on Tier II if the most you had on site at any one time last year met its threshold: 10,000 lb for most hazardous chemicals, and 500 lb or the Threshold Planning Quantity, whichever is lower, for Extremely Hazardous Substances. Quantities are totaled across the whole facility, including what sits inside mixtures.

The four thresholds

Source: 40 CFR 370.10. A "retail gas station" here means a facility selling fuel principally to the public for motor vehicles. A fleet yard or a contractor's private tank does not qualify, so its diesel falls under the 10,000 lb rule.

One more rule: if your SERC, LEPC or fire department asks you for Tier II information, the threshold becomes zero and you have 30 days to respond (40 CFR 370.10(b), 370.45(b)).

How to count

• Peak, not average. Use the most present on any single day during the calendar year.
• Whole facility. Add every container, tank and location on the site (contiguous or adjacent property under the same owner or operator counts as one facility; 40 CFR 370.3).
• Pounds, not gallons. Convert liquid volume to weight with the density or specific gravity on the SDS (40 CFR 370.43, note 1).
• Mixtures. You can count a mixture as a whole or count each hazardous component across all mixtures. Components at or below 1% (0.1% for carcinogens) don't have to be counted. EHS components must always be totaled across every mixture and pure product (40 CFR 370.14).

Worked examples

These examples use typical densities. Always use the figure on your own SDS.

Diesel fuel at a fleet yard

Diesel weighs roughly 7 lb per gallon, so 10,000 lb is about 1,400 gallons. A single 2,000-gallon tank that is ever more than about 70% full puts the site over the threshold.

Propane

Liquid propane is about 4.2 lb per gallon, so the 10,000 lb threshold is roughly 2,400 gallons of liquid. A 1,000-gallon tank alone is under; three of them may not be.

Lead-acid batteries (forklifts, UPS, telecom)

Batteries contain two reportable chemicals. Sulfuric acid is an EHS with a TPQ of 1,000 lb, so its Tier II threshold is 500 lb, the lower of the two. Lead uses the 10,000 lb threshold. Battery SDSs or manufacturer data give the weight of acid and lead per battery; multiply by the number of batteries on site. Large UPS rooms and forklift fleets often cross the 500 lb sulfuric acid line. (TPQ: 40 CFR part 355, appendix A.)

An EHS with a low TPQ

Chlorine has a TPQ of 100 lb, so it is reportable at 100 lb, not 500. A single one-ton chlorine cylinder at a water plant is far over.

What doesn't count

Products without an OSHA SDS requirement and the EPCRA exemptions are excluded: FDA-regulated food, drugs and cosmetics; solids in manufactured articles with no exposure in normal use; consumer-type products used the way consumers use them; research-lab and hospital use under a qualified person's supervision; and routine agricultural use (40 CFR 370.13). Many states add their own chemicals or lower thresholds, so check your state.

Sources

1. 40 CFR part 370, thresholds, mixtures and range codes
2. 40 CFR part 355, EHS list and TPQs
3. EPA, EPCRA Sections 311–312
4. EPA, Consolidated List of Lists

Related guides

• Threshold Planning Quantity (TPQ), explained
• Tier II reporting: what it is, who files, and when
• Tier II reporting requirements: what the form needs, field by field