UN 1021

1-CHLORO-1,2,2,2-TETRAFLUOROETHANE (REFRIGERANT GAS R 124)

UN 1021 — ADR 2025 Table A: class 2, classification code 2A, packing group —, labels 2.2, special provisions 662, limited quantity 120 ml, excepted quantity E1, packing instructions P200, transport category 3, tunnel restriction code (C/E), hazard identification number 20.

UNECE ADR 2025, ECE/TRANS/352 · checked 2026-10-28

Table A — ADR 2025 (ECE/TRANS/352), UN 1021
(1) UN No.1021
(2) Name and description1-CHLORO-1,2,2,2-TETRAFLUOROETHANE (REFRIGERANT GAS R 124)
(3a) Class2
(3b) Classification code2A
(4) Packing group—
(5) Labels2.2
(6) Special provisions662
(7a) Limited quantities120 ml
(7b) Excepted quantitiesE1
(8) Packaging: packing instructionsP200
(9a) Packaging: special packing provisions—
(9b) Packaging: mixed packing provisionsMP9
(10) Portable tanks and bulk containers: instructions(M) T50
(11) Portable tanks and bulk containers: special provisions—
(12) ADR tank: tank codePxBN(M)
(13) ADR tank: special provisionsTA4 TT9
(14) Vehicle for tank carriageAT
(15) Transport category (Tunnel restriction code)3 (C/E)
(16) Special provisions for carriage: packages—
(17) Special provisions for carriage: bulk—
(18) Special provisions for carriage: loading, unloading and handlingCV9 CV10 CV36
(19) Special provisions for carriage: operation—
(20) Hazard identification No.20

ADR 2027 (accepted) — what changes for UN 1021

ADR 2027 was accepted: depositary notification C.N.395.2026 (9 October 2026) records no objection to the amendments proposed by C.N.252.2026. It applies from 1 January 2027, and ADR 2025 may still be applied until 30 June 2027 (1.6.1.1). (C.N.395.2026)

UN 1021: Table A changes, ADR 2025 → ADR 2027
ColumnADR 2025 → ADR 2027Source
(13) ADR tank special provisionsTA4 TT9 → TA4 TT9 TM6ECE/TRANS/WP.15/274, PDF p. 15

ADR 2025 remains the edition FreightUtils serves and the one that applies until ADR 2027 takes effect on 1 January 2027; after that, ADR 2025 may still be applied until 30 June 2027 (1.6.1.1).

All ADR 2027 Table A changes →Check a list of UN numbers →

In plain words

Tunnels
Tunnel code (C/E): in tanks, Prohibited in C, D, E; in other carriage, Prohibited in E. Tanks: A, B. Packages: A, B, C, D. (ADR 8.6.4; from the ADR table itself)
Small-load exemption
Transport category 3: at most 1000 per transport unit under 1.1.3.6, counted ×1 toward the 1,000-point limit (ADR 1.1.3.6.3; from the ADR table itself)
Labels
Labels: model 2.2 (Gases: non-flammable, non-toxic gases) (ADR 5.2.2.2.2, label model No. 2.2; paraphrase, not yet reviewed)
Packing
Packing instruction P200: Gases in cylinders, tubes, pressure drums and bundles: closure, test pressure, filling limits, periodic inspection and per-gas provisions. Mixed packing provision MP9: May share a combination outer packaging with other Class 2 goods, with other classes that permit it, or with non-ADR goods. (ADR 4.1.4.1, P200, 4.1.10.4, MP9; paraphrase, not yet reviewed)
Tanks
Portable tank instruction (M): Marker in column (10): the substance may also be carried in UN MEGCs (multiple-element gas containers). Portable tank instruction T50: Per-gas portable tank table for non-refrigerated liquefied gases and chemicals under pressure (UN 3500–3505): MAWP, openings, relief, filling. Tank code PxBN(M): ADR tank code for Class 2 gases: liquefied/dissolved gas tank, X (test pressure from 4.3.3.2.5), openings B, valves/devices N, suffix (M). — P: tank, battery-vehicle or MEGC for liquefied or dissolved gases; X: the minimum relevant test pressure taken from the table in 4.3.3.2.5 for the gas; B: tank filled or discharged from the bottom through openings having 3 closures; or a battery-vehicle/MEGC with openings below the liquid surface or for compressed gases; N: safety valve conforming to 6.8.3.2.9 / 6.8.3.2.10 that is not hermetically closed; (M): the substance may also be carried in battery-vehicles or MEGCs (3.2.1, column (12)) Tank provision TA4: Conformity assessment under 1.8.7 by the competent authority or an inspection body to 1.8.6.3 accredited to EN ISO/IEC 17020:2012 type A. Tank provision TT9: Inspections and tests, including supervision of manufacture, under 1.8.7 by the competent authority or a type A accredited inspection body. Vehicle for tank carriage: AT — Tank vehicle for dangerous goods that is not EX/III, FL or a MEMU: tanks over 1 m³ / 3 m³, or battery-vehicle over 1 m³. (ADR 3.2.1, explanation of Column (10), 4.2.5.2.6, portable tank instruction T50, 4.3.3.1.1, tank code PxBN(M), 6.8.4 (c), TA4, 6.8.4 (d), TT9, 9.1.1.2, AT vehicle; paraphrase, not yet reviewed)
Carriage
Loading provision CV9: Do not throw packages or subject them to impact; stow receptacles so they cannot tip over or fall. Loading provision CV10: Cylinders lie along or across the vehicle axis (across at the front wall); stable or secured ones may stand; flat ones must be wedged. Loading provision CV36: Prefer open or ventilated units; if closed, isolate the cab from the load and mark doors "WARNING NO VENTILATION OPEN WITH CAUTION" (≥ 25 mm). (ADR 7.5.11, CV9, 7.5.11, CV10, 7.5.11, CV36; paraphrase, not yet reviewed)

Assembled from FreightUtils' meanings of the Table A codes, not the official text. A statement marked “not yet reviewed” has not yet been checked against ADR by a person.

Class 2 — Gases
UN 1021Class 2 — Gases
Packing Group
N/A
Not applicable
Classification Code
2A
Tunnel Code
(C/E) meaning →
Code governing tunnel passage
Transport Category
3
For the 1,000-point rule (0 = highest restriction)
Hazard ID No.
20
Kemler code
Limited Quantity
120 ml
Max per inner package for LQ relief
Excepted Quantity
E1
EQ code for excepted quantity relief
Thresholds — why, not just the verdict
Transport Category
Category 3
×1 points per kg/L — up to 1,000 kg/L of this substance alone stays under the 1,000-point threshold
Per-substance max
1,000 kg/L
Per-substance maximum for 1.1.3.6 relief (1.1.3.6.3)
Limited Quantity
120 ml
Max per inner packaging for LQ relief (Chapter 3.4)
Excepted Quantity
E1
Max 30 ml/g per inner, 1,000 ml/g per outer package (Chapter 3.5)
Tunnel Code
Governs which tunnel categories the load may pass
Special Provisions
SP 662
May alter scope or limits — full text in ADR 2025 Chapter 3.3
Hazard Labels Required
Label 2.2

These labels must be displayed on packages and vehicle placards in accordance with ADR 2025.

Special Provisions
SP 662

Refer to ADR 2025 Chapter 3.3 for full text of each provision.

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All Class 2 UN numbers →
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📅Data: UNECE ADR 2025 (ECE/TRANS/352), via EU Directive 2008/68/EC. Last verified October 2026

ADR reference data only. Classification is the consignor's legal responsibility. Consult a DGSA for compliance decisions.

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