Xylene shipping under UN 1307 / Class 3: Packing Group Assignment and DG Documentation requires the shipper to apply the UN 1307 entry exactly as listed in the applicable modal regulation and to verify the packing group by closed-cup flash-point testing. Commercial xylene is a mixture of ortho-, meta-, para-xylene and ethylbenzene; the closed-cup flash point of mixed xylene is normally reported between 25°C and 27°C. Under ADR Table A, UN 1307 XYLENES is assigned to Class 3, classification code F1, packing group III, label 3, limited quantity 5 L, and excepted quantity E1. The same UN number and proper shipping name appear in the IMDG Code Dangerous Goods List and in 49 CFR 172.101. A xylene shipment therefore shares a common flammable-liquid classification across road, sea and US domestic modes, but the transport document, segregation, tank instruction and placarding obligations are mode-specific.

What Transport Document Fields Are Legally Required for UN 1307?

For a packaged or tank-container road shipment under ADR, the dangerous goods transport document must follow the sequence in ADR 5.4.1.2.1. The minimum description is “UN 1307, XYLENES, Class 3, Packing Group III.” The shipper then adds the number and description of packages, such as “1 tank container” or “80 steel drums, 1H1, 200 L,” and the total quantity of xylene as net volume in litres or net mass in kilogrammes. The consignor and consignee names and addresses are required. For maritime shipments, the transport document must satisfy IMDG Code 5.4.1.4, which identifies the dangerous goods declaration and requires a signed certification or equivalent electronic record. US highway shipments must meet 49 CFR 172.202 and include the basic description in the order required by that section, together with an emergency response telephone number under 49 CFR 172.604. A measured flash point in the 25°C to 32°C range is often entered as supplementary information; it is not a substitute for the packing group entry but supports the Class 3 assignment during carrier review.

Containerized xylene movements under the IMDG Code should be documented with a dangerous goods declaration and, for cargo transport units, a container/vehicle packing certificate under IMDG Code 5.4.2. The assigned EmS schedules for UN 1307 are Fire Schedule F-E and Spillage Schedule S-D. Because xylene is an aromatic hydrocarbon, gasket and seal selection is an operational boundary; EPDM and natural rubber degrade and swell in continuous contact, while fluorocarbon rubber FKM and PTFE provide acceptable resistance in loading arms, pump seals and valve seats. Stainless steel 316L or lined carbon steel is specified for continuous wetted service, and conductive hoses with verified end-to-end continuity are used to avoid static accumulation. Terminal loading of road tankers typically operates at manifold pressures of 2.0 bar to 4.0 bar; high-level shut-off probes and vapour balancing are normally part of the tank-terminal interface. Published data for terminal-specific maximum flow rates varies by hose diameter and may be restricted by the terminal operating procedure rather than by the UN 1307 entry itself.

When Flash-Point Measurements and Isomer Ratios Keep the Shipment in PG III

The classification logic under ADR 2.2.3.1.3 and 49 CFR 173.120(b) places UN 1307 in Packing Group III because its closed-cup flash point is between 23°C and 60°C and its initial boiling point is above 35°C. Packing Group I applies only to Class 3 liquids with a flash point below 23°C and an initial boiling point at or below 35°C; Packing Group II applies when the flash point is below 23°C and the initial boiling point is above 35°C. Xylene boils between approximately 138°C and 144°C, so the initial boiling point does not control the assignment. Commercial mixed xylene reports a closed-cup flash point normally in the 25°C to 27°C range; ortho-xylene is reported near 32°C under ASTM D93, while meta- and para-xylene values are closer to 25°C. A batch blended with lower-flash aromatic naphtha or solvent may shift the result below 23°C; in that case the shipment would become PG II, the limited quantity would drop to 1 L, and the tank or package packing instructions would change. Shippers must therefore keep batch-specific flash-point data and compare it against the closed-cup method prescribed by the applicable regulatory code.

Because xylene is a low-conductivity flammable liquid, transfer operations require static control. NFPA 77 and API RP 2003 identify aromatic hydrocarbon solvents of this type as static accumulators. A splash-filled compartment or an unbonded filter housing can generate charge separation and create a flammable atmosphere at the liquid surface. Loading systems therefore specify an initial fill velocity at or below 1 m/s until the inlet is submerged, after which normal flow can be increased up to the terminal limit. Bonding and grounding connections are verified before the start of transfer; hoses with helical wire are inspected for continuity. The flammable range of mixed xylene is approximately 0.9 vol% to 7.0 vol%, which means vapour spaces inside storage and transport tanks are routinely within the flammable range unless inert gas blanketing is used. Nitrogen blanketing of ISO tank containers is an operational measure, not a UN 1307 requirement, but it changes vapour-space management and requires the shipper to coordinate pressure-relief device settings with the tank certificate.

Limited-Quantity Marking Thresholds and Excepted-Quantity Certification

ADR chapter 3.4 permits packaged xylene to be shipped as a limited quantity when the inner packaging contains no more than 5 L and the outer package gross mass does not exceed 30 kg. Under this relief, the outer package displays the limited-quantity marking instead of Class 3 labels, provided the total load remains below the per-transport-unit threshold in ADR 1.1.3.6. The dangerous goods transport document must still identify the goods as a limited quantity, and the shipper must not consolidate marked packages into a load that exceeds the exemption limit. Under ADR chapter 3.5, UN 1307 has excepted quantity code E1; the maximum net quantity per inner packaging is 30 mL and per outer packaging is 1000 mL. Excepted packages are not described as dangerous goods in the full sequence, but the outside of the package displays the UN number and class number in a visible location. These reliefs reduce labelling and documentation burden only for very small samples, not for normal drum, intermediate bulk container or tank-vehicle transport.

Packaging instruction P001 for PG III xylene permits single packagings such as steel drums, aluminium drums, plastics drums, jerricans and composite packagings, provided the materials are compatible with aromatic hydrocarbon attack; closures are specified as inert to the lading. Openings in packages must be closed with gaskets that do not soften under xylene exposure, and plastic closures should be tested for solvent permeation. Intermediate bulk containers under IBC03 are used for 1000 L rigid or composite IBCs; flexible IBCs are not acceptable for a liquid with this flash point. The marked UN specification plate on each package is therefore a prerequisite for DGD acceptance by the carrier.

Tank-container shipments of xylene require the DGD to list the tank as a package type and the net volume or mass as measured at the terminal. The ADR portable tank instruction T2 and the tank certificate define the minimum shell thickness, test pressure, relief-device setting, and periodic inspection intervals. A shipper should reject a tank with an expired five-year periodic inspection under ADR 6.8.2.4.2 because the tank certificate no longer supports the DGD statement. Similarly, a difference between the DGD quantity and the terminal meter ticket creates an auditable non-conformance; the DGD must be corrected before the vehicle leaves the terminal. The safety data sheet Section 14 should show exactly “UN 1307, Xylene, Class 3, Packing Group III,” but the SDS is not a substitute for the dangerous goods transport document.

Segregation of UN 1307 from Class 5.1 oxidizers and from sources of heat is a load-placement requirement. In a closed cargo transport unit, xylene vapours may accumulate; the unit should be ventilated according to route-specific requirements or treated as an unventilated mixed load. Because xylene has a vapour density of about 3.7 relative to air, vapours tend to collect near floor level and in low points. The DGD and the container/vehicle packing certificate therefore state that the packages were inspected for secure stowage and that closures were leak-free before sealing. Incompatible materials such as oxidizers must not be packed in the same unit unless separated by an intervening inert package or a physical barrier authorized by the applicable segregation table.

Air transport of xylene samples and small quantities is governed by the IATA Dangerous Goods Regulations with the same UN 1307, Xylenes, Class 3, Packing Group III sequence. The shipper must issue a signed Shipper’s Declaration for Dangerous Goods and observe the current IATA packing instruction and quantity limits for flammable liquids; many xylene shipments are permitted only on cargo aircraft because of accessible limit restrictions. Training and dangerous goods awareness records are required for personnel preparing the DGD, loading the cargo transport unit, and signing the packing certificate. The consignor remains responsible for the accuracy of the classification, packaging, marking and documentation even when a forwarder or logistics service provider completes part of the process. Document retention periods should be set to the route-specific regulation; under ADR, the operator retains the dangerous goods transport document in accordance with ADR 5.4.1.1 for at least 3 months after the carriage is complete.