No — acetone is exempt from the U.S. EPA definition of a volatile organic compound (VOC). The EPA excluded acetone from its regulatory VOC definition in 40 CFR 51.100(s) because acetone is negligibly photochemically reactive, meaning it makes a negligible contribution to ground-level ozone. This VOC exemption does not make acetone harmless: it remains a flammable liquid regulated by OSHA and DOT, with an OSHA permissible exposure limit of 1,000 ppm.
Is acetone a VOC under EPA rules?
Under federal Clean Air Act rules, acetone (CAS 67-64-1) is not counted as a VOC. The EPA maintains a list of compounds excluded from the regulatory definition of VOC in 40 CFR 51.100(s) because they are “negligibly reactive” — they contribute little to photochemical smog. The EPA added acetone to that list in 1995. As a result, acetone is widely used to reformulate coatings, adhesives, and cleaners to lower their regulated VOC content.
Two important limits apply to that exemption. First, the EPA exempts pure acetone as a compound; a product or mixture is not automatically VOC-exempt just because it contains acetone. Second, VOC exemption is only an air-quality/ozone classification — it does not remove acetone’s flammability, toxicity, or transport obligations. The EPA states plainly that exemption from the VOC definition does not exempt a compound from other regulation.
What is acetone’s regulatory status at a glance?
The table summarizes the key U.S. regulatory and hazard classifications for acetone. Confirm the current Safety Data Sheet (SDS) and the applicable federal, state, and local rules for your site before relying on any single value.
| Category | Classification for acetone |
|---|---|
| CAS number | 67-64-1 |
| Federal VOC status (EPA) | Exempt — 40 CFR 51.100(s), negligibly reactive |
| OSHA PEL (29 CFR 1910.1000) | 1,000 ppm (2,400 mg/m³), 8-hour TWA |
| NIOSH REL | 250 ppm (590 mg/m³), 10-hour TWA |
| NIOSH IDLH | 2,500 ppm |
| DOT shipping name | UN1090, Acetone, Class 3 flammable liquid, Packing Group II |
| RCRA hazardous waste | Ignitable waste D001; listed waste U002 as an unused discarded product |
| Flash point | −20 °C (−4 °F) — highly flammable |
Why is acetone exempt from the VOC definition?
The EPA regulates VOCs mainly because they react in sunlight with nitrogen oxides to form ground-level ozone (smog). Compounds that react more slowly than ethane are considered to have negligible photochemical reactivity, and the EPA can exclude them from the VOC definition. Acetone meets that test, so it was added to the list of exempt compounds in 40 CFR 51.100(s). For manufacturers, that means using acetone as a solvent can reduce a formulation’s regulated VOC content without necessarily reducing its solvency — a key reason acetone is common in low-VOC coatings and cleaners.
Does VOC-exempt mean acetone is unregulated or safe?
No. VOC exemption is narrow. Acetone remains subject to multiple other rules:
- Flammability (OSHA / NFPA / fire code): Acetone has a flash point of about −20 °C (−4 °F) and forms ignitable vapor at room temperature. It must be stored and handled as a flammable liquid, with grounding and bonding during transfer. See our guide on how to store acetone safely.
- Worker exposure (OSHA / NIOSH): The OSHA PEL is 1,000 ppm as an 8-hour TWA; NIOSH recommends a lower REL of 250 ppm.
- Transport (DOT): Acetone ships as UN1090, Class 3 flammable liquid, Packing Group II. See DOT hazmat classes for solvents.
- Waste (RCRA): Discarded acetone is an ignitable hazardous waste (D001), and unused product carries waste code U002.
In short, “VOC-exempt” describes acetone’s ozone-forming potential, not its overall hazard profile.
Do state and local rules also exempt acetone?
Most state and local air agencies follow the federal VOC definition, so acetone is generally treated as VOC-exempt for air-permit and coating-rule purposes nationwide, including in California. However, air rules vary by jurisdiction and by product category, and some consumer-product or architectural-coating regulations set their own limits. Always confirm the specific rule (federal, state, and local air district) that applies to your product and location before claiming a VOC-exempt status on a label or permit.
How do you read acetone’s hazard label and SDS?
Because acetone is flammable and an eye/respiratory irritant, its container label and SDS carry specific GHS pictograms and statements — typically the flame pictogram, “Danger,” and hazard statements for a highly flammable liquid and vapor. For a walkthrough of the symbols and signal words, see how to read a GHS label on a chemical drum. The authoritative physical and hazard data source is the PubChem record for acetone (CID 180), alongside the manufacturer SDS.
What grades and sizes of acetone does RightPath stock?
RightPath Industries supplies bulk acetone in technical/industrial and ACS reagent grades, with a batch Certificate of Analysis (COA) on every order. See the full solvents category for related products. Typical packaging includes 5-gallon pails, 55-gallon drums, 275- and 330-gallon IBC totes, and bulk tank truck or rail quantities, all shipped as UN1090 flammable liquid via licensed hazmat carriers.
How do you order bulk acetone from RightPath?
Tell us the grade, package size, and quantity you need, plus your delivery ZIP for freight. We confirm grade, COA, lead time, and DOT/hazmat logistics up front. Request bulk pricing and a RightPath specialist will match the acetone grade and packaging to your process and compliance needs.
Frequently asked questions
Is acetone a VOC?
No. Acetone is exempt from the U.S. EPA regulatory definition of a VOC under 40 CFR 51.100(s) because it is negligibly photochemically reactive. It is still a regulated flammable liquid.
Why is acetone not considered a VOC?
Acetone reacts too slowly in the atmosphere to contribute meaningfully to ground-level ozone, so the EPA classifies it as negligibly reactive and excludes it from the VOC definition.
What is the OSHA exposure limit for acetone?
The OSHA permissible exposure limit (PEL) for acetone is 1,000 ppm (2,400 mg/m³) as an 8-hour time-weighted average. NIOSH recommends a lower limit of 250 ppm.
Does VOC-exempt mean acetone is safe or unregulated?
No. VOC exemption only addresses ozone-forming potential. Acetone is still a highly flammable liquid regulated by OSHA for exposure, by DOT for transport (UN1090), and by RCRA as an ignitable waste.
Is acetone a VOC in California?
California and most state and local air agencies follow the federal exemption, so acetone is generally treated as VOC-exempt. Specific coating and consumer-product rules can still apply, so confirm the regulation for your product and location.