HazMat Tool — substance information

Water-reactive, solid, oxidizing, n.o.s

HMT 15 June 2026

UN / ID: UN 3133
Hazard class: 4.3
Packing group: II (multiple — see tabs)
ERG guide: ERG 138
Special provisions: —
Source: 49 CFR §172 (15 June 2026)

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Water-reactive, solid, oxidizing, n.o.s

Emergency Response Guide No. 138

Hazardous Materials Table

Source: 49 CFR §172 (15 June 2026)

Packing group II
Packing group III

(3) Hazard Class

4.3
Dangerous when wet materials

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)

(8) Packing Authorizations (§173.***)

(8A) Exceptions	151	see 49 CFR §173.151
(8B) Non-bulk	214	see 49 CFR §173.214
(8C) Bulk	214	see 49 CFR §173.214

(9) Quantity Limits

(9A) Passenger aircraft/rail	Forbidden
(9B) Cargo aircraft only	Forbidden

(10) Vessel stowage

(10A) Location

Stowage category “E” means the material may be stowed “on deck” or “under deck” 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 is prohibited from carriage on a passenger vessel in which the limiting number of passengers is exceeded.

Source: 49 CFR §172.101(k)

(10B) Other

13	see 49 CFR §176.84
40	see 49 CFR §176.84
148	see 49 CFR §176.84

Source: 49 CFR §176.84

(3) Hazard Class

4.3
Dangerous when wet materials

(4) Identification number

UN 3133

(5) Packing Group

III

Comparison View of PG

(6) Labels

(1) Symbols

(7) Special Provisions (§172.102)

(8) Packing Authorizations (§173.***)

(8A) Exceptions	151	see 49 CFR §173.151
(8B) Non-bulk	214	see 49 CFR §173.214
(8C) Bulk	214	see 49 CFR §173.214

(9) Quantity Limits

(9A) Passenger aircraft/rail	Forbidden
(9B) Cargo aircraft only	Forbidden

(10) Vessel stowage

(10A) Location

Source: 49 CFR §172.101(k)

(10B) Other

13	see 49 CFR §176.84
40	see 49 CFR §176.84
148	see 49 CFR §176.84

Source: 49 CFR §176.84

Packing group comparison

Multiple packing groups apply to this entry. See assignment criteria in 49 CFR §173 Subpart D. Details are in the tabs above; differences are highlighted.

	PG II	PG III
1	G	G
2	Water-reactive, solid, oxidizing, n.o.s	Water-reactive, solid, oxidizing, n.o.s
3	4.3	4.3
4	UN 3133	UN 3133
5	II	III
6	4.3, 5.1	4.3, 5.1
7	n/a	n/a
8A	151	151
8B	214	214
8C	214	214
9A	Forbidden	Forbidden
9B	Forbidden	Forbidden
10A	E	E
10B	13, 40, 148	13, 40, 148

Segregation chart for load, transport, and storage

This chart shows whether loading, transport, or storage with other hazard classes is permitted, prohibited, or restricted. Based on 49 CFR §177.848.

Hazard class	8	7	6.1	5.2	5.1	4.3	4.2	4.1	3	2.3B	2.3A	2.2	2.1	1.6	1.5	1.4	1.3	1.1/1.2
1.1/1.2
1.3
1.4
1.5
1.6
2.1
2.2
2.3A
2.3B
3
4.1
4.2
4.3
5.1
5.2
6.1
7
8

	Must not be loaded, transported, or stored together in the same vehicle or facility.
	May be loaded, transported, or stored together.
	May be loaded, transported, or stored together only with restrictions.

Similar substances

UN / ID	Proper shipping name	Hazard class
UN 3490	Toxic by inhalation liquid, water-reactive, flammable, n.o.s. with an LC50 lower than or equal to 200 ml/m3 and saturated vapor concentration greater than or equal to 500 LC50	6.1
UN 3491	Toxic by inhalation liquid, water-reactive, flammable, n.o.s. with an LC50 lower or equal to 1000 ml/m3 and saturated vapor concentration greater than or equal to 10 LC50	6.1
UN 3386	Toxic by inhalation liquid, water-reactive, n.o.s. with an LC50 lower than or equal to 1000 ml/m3 and saturated vapor concentration greater than or equal to 10 LC50	6.1
UN 3385	Toxic by inhalation liquid, water-reactive, n.o.s. with an LC50 lower than or equal to 200 ml/m3 and saturated vapor concentration greater than or equal to 500 LC50	6.1
UN 3476	Fuel cell cartridges or Fuel cell cartridges contained in equipment or Fuel cell cartridges packed with equipment, containing water-reactive substances	4.3
UN 3232	Self-reactive solid type B, temperature controlled	4.1
UN 3234	Self-reactive solid type C, temperature controlled	4.1
UN 3236	Self-reactive solid type D, temperature controlled	4.1
UN 3238	Self-reactive solid type E, temperature controlled	4.1
UN 3240	Self-reactive solid type F, temperature controlled	4.1
UN 3121	Oxidizing solid, water reactive, n.o.s	5.1
UN 3393	Organometallic substance, solid, pyrophoric, water-reactive	4.2
UN 3394	Organometallic substance, liquid, pyrophoric, water-reactive	4.2
UN 3231	Self-reactive liquid type B, temperature controlled	4.1
UN 3233	Self-reactive liquid type C, temperature controlled	4.1