UN1090 acetone decoder.

The UN1090 row in the Hazardous Materials Table

The table below is 49 CFR 172.101 as published in the eCFR, current through October 29, 2026, for UN1090. Columns are: class (3), packing group (5), label codes (6), special provisions (7), packaging exceptions (8A), non-bulk packaging (8B), bulk packaging (8C), quantity limits for passenger aircraft or railcar (9A) and cargo aircraft only (9B), and vessel stowage (10A and 10B). There is one row.

Reading the packaging columns

Columns 8A to 8C do not hold rules themselves; they point to sections of part 173. For this entry they point to:

• 173.150: Exceptions for Class 3 (flammable and combustible liquids).
• 173.202: Non-bulk packagings for liquid hazardous materials in Packing Group II.
• 173.242: Bulk packagings for certain medium hazard liquids and solids, including solids with dual hazards.

Exceptions in column 8A apply only if that section is referenced for the specific material in the table, so a limited quantity route that exists for one UN number is not automatically open to another.

Special provisions on this entry

The letter prefixes on special provisions tell you where each applies (172.102(c)): a code of only numbers is multi-modal; "A" applies only to transportation by aircraft; "B" only to bulk packaging; "IB" and "IP" only to IBCs; "N" only to non-bulk packaging; "T" and "TP" only to UN portable tanks.

• IB2: Authorized IBCs: metal (31A, 31B, 31N), rigid plastic (31H1, 31H2) and composite (31HZ1).
• T4: a portable tank instruction. It set the minimum test pressure, shell thickness, bottom opening and pressure relief requirements for UN portable tanks.
• TP1: The maximum degree of filling of a portable tank must not exceed the figure from the formula given in the provision.

What the short special provisions list means

The acetone row is short: IB2, T4 and TP1. IB2 names the authorized IBCs (metal 31A, 31B and 31N; rigid plastic 31H1 and 31H2; composite 31HZ1). T4 is the portable tank instruction, which sets the test pressure, shell thickness, bottom opening and pressure relief rules for a UN portable tank, and TP1 limits how full the tank may be filled under the formula in the provision. There is no B code, so the bulk packaging rules come straight from 173.242 without a cargo tank exclusion list.

Water-miscible: why Guide 127 and not 128

ERG 2024 splits flammable liquids by how they behave in water. Acetone sits in Guide 127, Flammable Liquids (Water-Miscible), which is paired with Guide 128 for water-immiscible liquids such as gasoline. The practical difference is in the fire response: Guide 127 recommends dry chemical, CO2, water spray or alcohol-resistant foam on a small fire, and water spray, fog or alcohol-resistant foam on a large one, while Guide 128 allows regular foam. The guide also cautions that most of the products have a very low flash point, so water spray may be inefficient.

Limited quantity packages

Column 8A shows 150, so the 173.150 exceptions are available. For a Packing Group II Class 3 liquid, 173.150(b) limits inner packagings to 1.0 L (0.3 gallon) in a combination package of 30 kg (66 pounds) gross weight or less. Limited quantity packages are not subject to the placarding subpart, and the exception applies only because 173.150 is referenced for this entry. Vessel stowage category in column 10A is B, and column 10B is blank.

ERG 2024 Guide 127: Flammable Liquids (Water-Miscible)

The ERG 2024 numerical index lists UN1090 against Guide 127. The guide appears on pages 183 to 184 of the 2024 guidebook. The guidebook is meant for first responders during the initial phase of an incident, and it says to call 911 and then the emergency response telephone number on the shipping paper.

• Fire or explosion: "HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames." Vapors may form explosive mixtures with air, may travel to a source of ignition and flash back, and most are heavier than air, collecting in low or confined areas such as sewers and basements.
• Health: inhalation or contact may irritate or burn skin and eyes, and vapors may cause dizziness or asphyxiation in closed or confined areas.
• Evacuation: isolate a spill or leak area for at least 50 meters (150 feet) in all directions; for a large spill consider initial downwind evacuation of at least 300 meters (1000 feet); for a tank, rail tank car or highway tank in a fire, isolate for 800 meters (1/2 mile).
• Fire response: the guide cautions that most of these products have a very low flash point, so water spray may be inefficient. Small fire, dry chemical, CO2, water spray or alcohol-resistant foam; large fire, water spray, fog or alcohol-resistant foam, avoiding straight or solid streams onto the product.
• Spill: eliminate ignition sources, ground all equipment used when handling the product, do not touch spilled material, prevent entry into waterways, sewers, basements or confined areas, and use vapor-suppressing foam to reduce vapors.

The guide is a starting point until the material is identified. Read the full guide in the current ERG, and use the shipping paper emergency number for product-specific advice.

Placards, quantity and vessel stowage

3 is a Table 2 category in 172.504(e), so the placard is FLAMMABLE. On a highway vehicle with less than 454 kg (1,001 pounds) aggregate gross weight of Table 2 materials in non-bulk packages, no placard is required, but bulk packagings and materials subject to 172.505 are not eligible for that exception (172.504(c)).

Vessel stowage is the category in column 10A (B), which the table sets for this entry, plus the column 10B codes. Column 10B is blank for this entry. Hazmat shipped as a limited quantity is allocated stowage category A and is not subject to the column 10B stowage codes (176.63(a)).

Worked example

A print shop sends a case of six 1 L bottles of acetone cleaner by highway. Each inner packaging is 1.0 L, so the case fits the Packing Group II limited quantity limit in 173.150(b) if it is a compliant combination packaging of 30 kg (66 pounds) gross weight or less. The same six liters by passenger aircraft is 6 L net, over the 5 L column 9A limit; by cargo aircraft only it is within the 60 L limit. A pickup carrying 800 pounds of UN1090 in non-bulk cartons is under the 1,001 pound threshold in 172.504(c), so no FLAMMABLE placard is required.

Limits

This page reads the 172.101 table, the 172.102 special provisions, 172.504 and the section titles named above, plus ERG 2024. It does not classify your material, choose a proper shipping name, or build shipping papers, marks, labels or training requirements. The checker compares your net quantity to the printed column 9A and 9B limits and applies the 1,001 pound rule to the class on the row; it does not model subsidiary hazard placards (172.505), mixed loads, state rules or carrier restrictions. Special provisions are shown in summary; read the full text in 172.102 before relying on one. Hazmat shipping needs trained hazmat employees (49 CFR part 172, subpart H).

Sources

Sources opened and read November 2, 2026.

• eCFR: 49 CFR 172.101, Hazardous Materials Table (current through October 29, 2026) (read November 2, 2026)
• eCFR: 49 CFR 172.102, special provisions (current through October 29, 2026) (read November 2, 2026)
• eCFR: 49 CFR 172.504, general placarding requirements (current through October 29, 2026) (read November 2, 2026)
• eCFR: 49 CFR 173.150, Exceptions for Class 3 (flammable and combustible liquids) (current through October 29, 2026) (read November 2, 2026)
• eCFR: 49 CFR 173.202, Non-bulk packagings for liquid hazardous materials in Packing Group II (current through October 29, 2026) (read November 2, 2026)
• eCFR: 49 CFR 173.242, Bulk packagings for certain medium hazard liquids and solids, including solids with dual hazards (current through October 29, 2026) (read November 2, 2026)
• eCFR: 49 CFR 176.84, other requirements for stowage, cargo handling and segregation (current through October 29, 2026) (read November 2, 2026)
• eCFR: 49 CFR 176.63, stowage locations (current through October 29, 2026) (read November 2, 2026)
• PHMSA: Emergency Response Guidebook (ERG) landing page (read November 2, 2026)
• PHMSA: ERG 2024 PDF, numerical index and guide pages (the phmsa.dot.gov host refused automated requests; the Internet Archive copy of this file was read) (read November 2, 2026)