HazMat Tool — substance information

Flammable solids, corrosive, organic, n.o.s.

HMT 15 June 2026

UN / ID: UN 2925
Hazard class: 4.1
Packing group: II (multiple — see tabs)
ERG guide: ERG 134
Special provisions: SP A1, SP IB6, SP IP2, SP T3, SP TP33
Source: 49 CFR §172 (15 June 2026)

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Flammable solids, corrosive, organic, n.o.s.

Flammable Solids are: Wetted explosives that are Class 1 explosives when dry, that are sufficiently wetted to suppress explosive properties.; Self-reactive materials that are thermally unstable and can undergo strong exothermic decomposition even in the absence of oxygen. Readily combustible solids that can cause fire through friction, such as matches. Powdered, granular or pasty materials must be classified as Division 4.1 when the time of burning of one or more of the test runs, per the UN Manual of Tests and Criteria, is less than 45 seconds or the rate of burn is more than 2.2 mm/sec. Powders of metals or metal alloys are classified as Division 4.1 when they can be ignited and the reaction spreads over the whole length of the sample in = 10 minutes More Information

Emergency Response Guide No. 134

Hazardous Materials Table

Source: 49 CFR §172 (15 June 2026)

Packing group II
Packing group III

(3) Hazard Class

4.1
Flammable solids

(4) Identification number

UN 2925

(5) Packing Group

Comparison View of PG

(6) Labels

(1) Symbols

This entry is signed with "G". The letter "G" identifies proper shipping names for which one or more technical names of the hazardous material must be entered in parentheses, in association with the basic description. (See §172.203(k)).

(7) Special Provisions (§172.102)

×Note:
Special provisions may be very complex. The extracts are taken from 49 CFR §172.102. Please be careful with the information, as necessary, additional conditions may be applied that are not written here. Please check the original source and report bugs.

Single packagings are not permitted on passenger aircraft.

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IB6

_{Authorized IBCs:} Metal (11A, 11B, 11N, 21A, 21B, 21N, 31A, 31B and 31N); Rigid plastics (11H1, 11H2, 21H1, 21H2, 31H1 and 31H2); Composite (11HZ1, 11HZ2, 21HZ1, 21HZ2 and 31HZ1).
_{Additional Requirement:} Composite IBCs 11HZ2 and 21HZ2 may not be used when the hazardous materials being transported may become liquid during transport.

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IP2

When IBCs other than metal or rigid plastics IBCs are used, they must be offered for transportation in a closed freight container or a closed transport vehicle.

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Minimum test pressure (bar)	2.65
Minimum shell thickness	§ 178.274(d)(2)
Pressure-relief requirements	Normal
Bottom opening requirements	§ 178.275(d)(2)

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TP33

The portable tank instruction assigned for this substance applies for granular and powdered solids and for solids which are filled and discharged at temperatures above their melting point which are cooled and transported as a solid mass. Solid substances transported or offered for transport above their melting point are authorized for transportation in portable tanks conforming to the provisions of portable tank instruction T4 for solid substances of packing group III or T7 for solid substances of packing group II, unless a tank with more stringent requirements for minimum shell thickness, maximum allowable working pressure, pressure-relief devices or bottom outlets are assigned in which case the more stringent tank instruction and special provisions shall apply. Filling limits must be in accordance with portable tank special provision TP3. Solids meeting the definition of an elevated temperature material must be transported in accordance with the applicable requirements of this subchapter.

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(8) Packing Authorizations (§173.***)

(8A) Exceptions	151	see 49 CFR §173.151
(8B) Non-bulk	212	see 49 CFR §173.212
(8C) Bulk	242	see 49 CFR §173.242

(9) Quantity Limits

(9A) Passenger aircraft/rail	15 kg
(9B) Cargo aircraft only	50 kg

(10) Vessel stowage

(10A) Location

Stowage category “D” means the material must be stowed “on deck only” on a cargo vessel or on a passenger vessel carrying a number of passengers limited to not more than the larger of 25 passengers or one passenger per each 3 m of overall vessel length, but the material is prohibited on a passenger vessel in which the limiting number of passengers is exceeded.

Source: 49 CFR §172.101(k)

(10B) Other

40	see 49 CFR §176.84

Source: 49 CFR §176.84