UN1203 gasoline decoder.

The UN1203 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 UN1203. 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.

• 144: If transported as a residue in an underground storage tank cleaned and purged or rendered inert per API Standard 1604, the tank and the material are not subject to the other requirements of the subchapter; sediment that itself meets a hazardous material definition still is.
• 177: Gasoline, or ethanol and gasoline mixtures, for use in internal combustion engines must be assigned to Packing Group II regardless of variations in volatility.
• B1: If the flash point is at or above 38 degrees C (100 degrees F) and below 93 degrees C (200 degrees F), the bulk packaging requirements of 173.241 apply; below 38 degrees C (100 degrees F), 173.242 applies.
• B33: MC 300, 301, 302, 303, 305 and 306 and DOT 406 cargo tanks with a 1 psig normal vent used to carry gasoline must conform to Table I of the provision, which caps lading pressure and ambient temperature during loading by Reid vapor pressure volatility class.
• 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.

Special provision 177: always Packing Group II

Provision 177 says gasoline, or ethanol and gasoline mixtures, for use in internal combustion engines (for example in automobiles and stationary engines) must be assigned to Packing Group II regardless of variations in volatility. That removes the flash point and boiling point sorting that applies to other Class 3 liquids under 173.121. The entry text also covers gasoline mixed with ethyl alcohol with not more than 10 percent alcohol. Casinghead gasoline and motor spirit are cross-references: in ERG 2024 the index lists Gasoline, Motor spirit and Petrol against UN1203 and Guide 128.

Cargo tank rules: B1 and B33

Two bulk provisions apply. B1 sends bulk packaging to 173.241 when the flash point is at or above 38 degrees C and below 93 degrees C and to 173.242 below 38 degrees C. B33 covers MC 300, 301, 302, 303, 305 and 306 and DOT 406 cargo tanks with a 1 psig normal vent used to carry gasoline: they must conform to Table I of the provision, which limits the maximum lading pressure and maximum ambient temperature during loading according to the Reid vapor pressure volatility class determined under ASTM D 439. Column 10A gives stowage category E.

Underground storage tank residue (144)

Provision 144 lets a cleaned and purged underground storage tank, as defined in 40 CFR 280.12, carry gasoline residue without the tank or the material being subject to the rest of the subchapter, if it is cleaned and purged or rendered inert according to API Standard 1604. Sediment that itself meets a hazardous material definition remains regulated. It is the provision behind tank removal jobs.

Gasoline dispensers and the placard rule

Section 173.150(h) allows gasoline (UN1203) and diesel fuel to be transported one way, by motor vehicle, directly from the loading location to an equipment repair facility, in a non-DOT specification non-bulk packaging known as a gasoline dispenser that has been removed from service at a fueling station. Each dispenser must have all product inlet and outlet piping capped or plugged, may not contain more than 2 gallons of gasoline, and must be blocked, braced or strapped to prevent shifting.

Class 3 is a Table 2 category, so on a highway vehicle with less than 1,001 pounds (454 kg) aggregate gross weight of Table 2 materials in non-bulk packages no placard is required, and bulk packagings are placarded at any quantity (172.504(c)). Guide 128 is the guide for the response: isolate 50 meters (150 feet), consider downwind evacuation of at least 300 meters (1000 feet) for a large spill, and 800 meters (1/2 mile) for a tank in a fire.

ERG 2024 Guide 128: Flammable Liquids (Water-Immiscible)

The ERG 2024 numerical index lists UN1203 against Guide 128. The guide appears on pages 185 to 186 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. Many of these liquids float on water, and the guide notes the substance may be transported hot.
• Health: inhalation or contact may irritate or burn skin and eyes; fire may produce irritating, corrosive or toxic gases; vapors may cause dizziness or asphyxiation in 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: small fire, dry chemical, CO2, water spray or regular foam (alcohol-resistant foam if regular foam is ineffective or unavailable); large fire, water spray, fog or regular foam. For mixtures containing alcohol or a polar solvent, alcohol-resistant foam may be more effective.

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 (E), 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 landscaping crew carries ten 5-gallon (about 19 L) cans of gasoline on a pickup. Ten cans are about 190 L, and at roughly 6 pounds per gallon and 50 gallons that is about 300 pounds of product before can weight, well under 1,001 pounds, so the Table 2 exception in 172.504(c) applies and no FLAMMABLE placard is required for non-bulk packages. The product weight is an estimate for illustration; the weight that counts is the aggregate gross weight. A single 19 L can on a passenger aircraft is over the 5 L column 9A limit.

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)